Chapter XXVI: Appendix: To the Fishes: Palaeospondylidae—ostracodermi—heterostraci (7)

A beak; spinous dorsal and ventrals absent; pelvis movable
2. _Triodontidae_.

Teeth separate; spinous dorsal present; ventrals absent or
represented by a single short spine; pelvis movable
3. _Balistidae_.

B. Body encased in a carapace; no epipleurals; spinous dorsal,
pelvis, and ventrals absent 4. _Ostraciontidae_.

II. GYMNODONTES.—Supraclavicle oblique or nearly horizontal; lower{722}
three pterygials enlarged and immovably united to the coraco-scapular
cartilage; anterior vertebrae with bifid divergent neural spines;
pelvis absent.

Beak with a median suture; interoperculum not connected with
suboperculum; caudal fin present; body inflatable.
1. _Tetrodontidae_.

Beak without median suture; interoperculum attached posteriorly to
suboperculum; caudal fin present; body inflatable.
2. _Diodontidae_.

Beak without median suture; interoperculum attached posteriorly to
suboperculum; caudal fin absent, the body non-inflatable,
truncate posteriorly, with the dorsal and anal fins confluent.
3. _Molidae_.

DIVISION I.—SCLERODERMI.

Supraclavicle vertical; pectoral pterygials not enlarged, movably attached by ligament to the scapula and coracoid, three to the former and one to the latter. All the vertebrae with the neural arches forming a single spine. Basis cranii more or less distinctly double; dentary and articular completely co-ossified.

FAM. 1. TRIACANTHIDAE.—Praemaxillaries protractile, free from the maxillaries; teeth in the jaws separate, conical or incisor-like; palatine arch firmly united to the skull. Gills 4. Praecaudal vertebrae with parapophyses; epipleurals present. Spinous dorsal fin with 2 to 6 spines. Ventral fins each represented by a strong spine, with an inner basal knob which locks it when everted, rarely with the addition of 1 or 2 rudimentary soft rays; pelvis present, firmly united to the pectoral arch. Scales small, sometimes spinous or bony. Vertebrae 20.

Marine fishes from the Indian and Western Pacific Oceans. Ten species, referable to three genera: _Triacanthus_, _Triacanthodes_, {723}_Halimochirurgus_. The latter, remarkable for its long, tube-like snout, is the only deep-sea form of this Sub-order; it was recently discovered in the Gulf of Manaar, at a depth of 143 fathoms. Fossil genera are _Acanthopleurus_, Oligocene, and _Spinacanthus_, Eocene.

FAM. 2. TRIODONTIDAE.—Praemaxillaries not protractile, firmly united to the maxillaries; teeth coalescent into a beak, the upper jaw divided by a median suture, the lower simple. Praecaudal vertebrae with or without parapophyses; epipleurals present. No spinous dorsal fin. No ventral fins. Abdomen with a dilatable sac, kept expanded by the very long movable pelvis. Body covered with small, spiny, subimbricate, bony laminae. Vertebrae 20.

A single species, the curious _Triodon bursarius_ of the Indian Ocean and Archipelago.

FAM. 3. BALISTIDAE.—Praemaxillaries not protractile, firmly united to the praemaxillaries; teeth incisor-like; palatine movably articulated with ectopterygoid, or entirely free from it. Gills 4. Praecaudal vertebrae with well-developed parapophyses, to which epipleurals are attached. Spinous dorsal fin with 1 to 3 spines. Ventral fins, if present, represented by a single short {724}rough spine at the end of the long, movable pelvis. Body covered with juxtaposed movable scutes or with minute rough scales.

About 100 species are known from the tropical and warm seas, one species (_Balistes capriscus_) occasionally wandering as far north as the south coast of England. Genera: _Balistes_, _Monacanthus_, _Paraluteres_, _Pseudaluteres_, _Pseudomonacanthus_, _Aluteres_, _Psilocephalus_. The Oligocene genus _Acanthoderma_ is closely allied to _Balistes_.

The "File-Fishes" or "Trigger-Fishes" (_Balistes_), the largest species of which grow to nearly 3 feet, have a powerful dentition, which enables them to break off pieces of corals, on which they feed, and to bore holes in the hard shells of Mollusca in order to extract the soft parts; they are themselves well protected by a mail of hard, rhomboidal scales. The herbivorous _Monacanthus_ is less favoured in this respect, the rough scales being so small as to give the skin a velvety appearance.

_Psilocephalus_ differs from _Monacanthus_ in its very elongate head and body, the very feeble dorsal spine, the presence of a mental barbel, and its more numerous vertebrae (29 or 30 instead of 18 to 21). The flesh of many of these fishes is poisonous.[760] The drumming sounds produced by _Balistes_ have been described by Möbius.[761]

FAM. 4. OSTRACIONTIDAE.—Praemaxillaries not protractile, firmly united to the praemaxillaries; teeth incisor-like; palatine immovable. Gills 4. Praecaudal vertebrae with very feeble parapophyses and no epipleurals. No spinous dorsal fin. Clavicles, coracoids, and post-clavicles much expanded. No ventral fins. Body encased in a carapace formed of large, juxtaposed, mostly hexagonal bony plates. Vertebrae 14 to 16.

The species of "Trunk-Fishes" number about 20, and are referable to 3 genera: _Aracana_, _Ostracion_, _Lactophrys_; all belong to the tropical seas, living near the bottom in shallow water. The genus _Ostracion_ is represented by one species in the Upper Eocene.

The rigid box in which these fishes are encased entails more use of the dorsal and anal fins for progression than is customary {725}among fishes. According to Brown Goode, "the propelling force is exerted by the dorsal and anal fins, which have a half rotary, sculling motion, resembling that of a screw propeller; the caudal fin acts as a rudder, save when it is needed for unusually rapid swimming, when it is used as in other fishes; the chief function of the broad pectorals seems to be that of forming a current of water through the gills, thus aiding respiration, which would otherwise be difficult on account of the narrowness and inflexibility of the branchial apertures. When taken from the water, one of these fishes will live for two or three hours, all the time solemnly fanning its gills, and when restored to its native element seems none the worse for its experience, except that, on account of the air absorbed, it cannot at once sink to the bottom." "No group of tropical fishes," says the same author, "is so thoroughly worked out in the writings of the fathers of natural history as this one. Over 200 years ago every species of trunk-fish now taken from the Atlantic was known to and described by the naturalists, and it is a well-deserved tribute to their discrimination as zoologists to say that none of the many efforts which have since been made to subdivide their species have been at all successful."

DIVISION II.—GYMNODONTES.

Supraclavicle oblique, sometimes nearly horizontal; lower three pectoral pterygials enlarged and immovably united to the coracoscapular cartilage; upper pterygial small, suturally united to the scapula. Anterior vertebrae with bifid divergent neural spines. Basis cranii simple; suture between dentary and articular evident. Pelvis absent.

The spinous dorsal and the ventral fins are constantly absent, the praemaxillaries are united to the maxillaries, and the teeth {726}are coalescent, forming a beak; parapophyses are not developed, and epipleurals are absent.

FAM. 1. TETRODONTIDAE.—Beak with a median suture. Interoperculum a long rod, attached to inner face of praeoperculum, sometimes connected with operculum, never with suboperculum. Gills 3. First 4 or 5 praecaudal vertebrae with bifid neural spine and closed neural arch. Skin naked or with movable spines, rarely with bony plates; belly inflatable. Vertebrae 17 to 29.

The "Puffers" or "Globe-Fishes" comprise about 60 species, referable to 5 genera: _Tetrodon_, _Ephippion_, _Tropidichthys_, _Xenopterus_, _Chonerhinus_. They inhabit all the tropical and warm seas, a few species being confined to fresh water. Remains of _Tetrodon_ have been found in Upper Eocene and later formations. They are remarkable for the manner in which they inflate themselves with air.[762] The flesh of most species is poisonous.

FAM. 2. DIODONTIDAE.—Beak without median suture. Interoperculum rod-like, attached posteriorly to the rod-like anterior limb of the suboperculum. Gills 3. All the praecaudal vertebrae with bifid neural spines. Skin with movable spines; belly inflatable. Vertebrae 21 or 22.

Only two genera appear capable of clear definition: _Diodon_ and _Lyosphaera_; species about 15. Numerous species have been described from the Upper Eocene and later formations.

"Porcupine Fishes" are confined to tropical seas, and have attracted attention from the earliest times, being frequently preserved as "curiosities." Their flesh is regarded as poisonous.

FAM. 3. MOLIDAE.—Beak without median suture. Interoperculum rod-like, attached posteriorly to the rod-like anterior limb of the suboperculum. Gills 4. Anterior praecaudal vertebrae with divergent bifid neural spines and neural canal not roofed in. {727}Body non-inflatable, truncate posteriorly, without caudal peduncle; caudal fin absent, the dorsal and anal fins confluent. Skin rough or tessellated. Vertebrae 17 in _Orthagoriscus_.

The very young are armed with spines.

The "Sun-Fish" are extraordinary creatures found in the open sea or descending to great depths, and of wide distribution. The number of species is still very uncertain, but two generic forms, _Orthagoriscus_ or _Mola_ and _Ranzania_, are easily distinguished. Examples of both occur now and then on our coasts. _Orthagoriscus mola_ grows to upwards of 8 feet and to a weight of 1800 pounds. It has been observed to swim slowly about, near the surface, the high dorsal above the water. Its food is said to consist chiefly of jelly-fish and larval fishes; its mode of reproduction and places of breeding are still unknown.

{729}INDEX

Every reference is to the page: words in italics are names of genera or
species; figures in italics indicate that the reference relates to
systematic position; figures in thick type refer to an illustration; f. =
and in following page or pages; n. = note.

Abbott, 193 n.
_Abcona_, _670_
Abdominal pores, 401 f.
_Abramis_, _582_
_Abyssascidia_, _73_
_Acanthaphritis_, _706_
_Acanthias_, _455_, 298;
vertebral column, 198;
uterine nutrition, 434;
_A. vulgaris_, 264, 455;
pectoral fin, 243
_Acanthicus_, _595_
_Acanthistius_, _659_
_Acanthocepola_, _662_
_Acanthoclinus_, _709_
_Acanthocybium_, _678_
Acanthodei, _440_ f., 148
_Acanthoderma_, _724_
_Acanthodes_, _442_;
_A. wardi_, 441
Acanthodidae, _441_
_Acanthodopsis_, _442_
_Acanthonus_, _712_
_Acanthophthalmus_, _582_
_Acanthopleurus_, _723_
_Acanthopoma_, _589_
Acanthopterygii, _650_ f., 159, 306, 543;
diagram showing relationships of groups, 651
Acanthuridae, _668_, 357, 651, 652, 654
_Acanthurus_, _668_;
_A. chirurgus_, 357
_Acara_, _672_
Accessory respiratory organs, 292
_Acentronura_, _634_
_Acentrophorus_, _498_
_Aceratias_, _719_
_Acerina_, _659_;
_A. cernua_, 659
_Acestra_, _595_;
_A. gladius_, 595
_Acestrorhamphus_, _575_
_Acestrorhynchus_, _575_
_Achilognathus_, _582_
_Achiropsis_, _687_
_Achirus_, _687_
_Acipenser_, _492_, 149, 262, 264, 273, 274, 276, 282, 348;
ribs, 201;
lymph follicles, 261;
spiral valve, 268;
gills, 283, 284;
air-bladder, 298, 299;
vascular system, 319, 322, 328, 334;
spleen, 343;
gonoducts of female, 400, 405;
distribution, habits, and food, 493;
breeding, 494;
economic value, 494;
_A. huso_, 494;
_A. rhynchaeus_, pectoral fin, 243;
_A. ruthenus_, 493;
scales, 187, 188;
brain, 376;
micropyles, 411;
larva, 494;
_A. sturio_, 493, 494;
vertebral column, 200;
supra-renals, 346;
micropyles, 411
Acipenseridae, _486_, 489, 495
Acipenseroidei = Chondrostei, _q.v._
Acrania, _113_
Acrartete, 636 n.
_Acrochordonichthys_, _588_
_Acrodus_, _445_
_Acrogaster_, _656_
_Acrognathus_, _611_
_Acropoma_, _659_
Acropomatidae, _659_, 654
_Acrotus_, _644_
Actinistia, _477_ n.
Actinopterygii, _476_
Actinotrocha, 28 f., 29
_Acysis_, _588_
Adipose fins, 163
_Aegaeonichthys_, _719_
_Aelurichthys_, _588_
_Aethalion_, _546_
_Aetheolepis_, _498_;
scales, 187
Aetheospondyli, _497_
_Aëtobatis_, _465_, 466;
spines, 177
Agassiz, 558 n., 685 n., 720 n.
_Ageniosus_, _589_;
_A. valenciennesi_, 589
Agnathostomata, _145_;
characters of, 147
_Agoniates_, _575_
Agonidae, _700_, 694
_Agonopsis_, _700
Agonus_, _700_; {730}
_A. cataphractus_, 700
_Agrammus_, _696_
_Agriopus_, _695_
_Aida_, _639_
_Ailia_, _588_;
air-bladder, 302
_Ailiichthys_, _588_
_Aipichthys_, _666_
Air-bladder, as an accessory respiratory organ, 291 f.;
_Amia_, 291;
_Lepidosteus_, 291, 299;
_Sudis gigas_, 291;
_Erythrinus taeniatus_ and _E. braziliensis_, 291;
_Neoceratodus_, 291, 300;
_Protopterus_, 291, 301, 302;
_Lepidosiren_, 291;
structure, 297;
in different Fishes, 298;
"red bodies," 307;
"red glands," 307, 308, 309;
gases of the air-bladder, 309;
functions, 309;
in locomotion, 310;
as a vocal organ, 358;
connexion with the auditory organ, 388, 389, 390
_Albula_, _548_, 541, 549;
vestigial conus arteriosus, 329, 548;
_A. conorhynchus_, 548;
larva, 548
Albulidae, _547_, 544
_Alburnus_, _582_;
_A. lucidus_, 167, 583
Alcock, 695
Alder and Hancock, 38
Alepidosauridae, _614_, 606
_Alepidosaurus_, _614_;
_A. ferox_, 614
Alepocephalidae, _569_, 544
_Alepocephalus_, _570_;
_A. rostratus_, 570 n.
_Aleposomus_, _570_
_Alestes_, _575_
Alimentary canal, of Hemichordata, 11, 25;
of Tunicata, 54, 67;
of Amphioxus, 120;
of Fishes, 252 f.;
regions, 252;
mesenteries, 258;
histology, 259 f.;
glands, 270
_Allabenchelys_, _588_
Allis Shad, 564
Allman, 22 n., 705 n.
_Alopecias vulpes_, _451_, 452;
spiral valve, 265
_Aluteres_, _724_
_Amaroucium_, _88_;
_A. proliferum_, stomach, 88
Ambassinae, _660_
_Ambassis_, _660_
_Ambloplites_, _657_
_Amblyapistus_, _695_
Amblyopsidae, _618_, 361, 395, 606
_Amblyopsis_, _618_;
_A. spelaea_, 166, 361, 618, 619
_Amblyopus_, _689_
_Amblypharyngodon_, _582_
_Amblypterus_, _487_
_Amia_, _499_, 149, 160, 262, 273, 274, 276, 283, 291, 393, 609 n.;
fossil, 501;
_A. calva_, 499, 500;
scales, 189;
vertebral column, 201, 202, 203;
skull, 228;
median fins, 235;
pectoral fin, 243, 244;
spiral valve, 268;
pseudobranch, 284;
air-bladder, 297, 299, 310;
heart, 328;
arteries to air-bladder, 337;
sensory canal, 385;
nephrostomes, 401, 402;
segmentation of ova, 409;
distribution and habits, 499;
spawning, 500;
nest, 500, 501;
larvae, 501
Amiidae, _499_, 299, 497
_Amiopsis_, _501_
_Amiurus_, _588_, 261;
liver and pancreas, 273;
_A. catus_, rectal valve, 254;
renal portal system, 319;
_A. nebulosus_, 587 n., 592;
_A. nigrilabris_, blind, 394
Ammocoetes, _428_, 46, 262, 272, 280, 280 n., 327, 343, 428;
metamorphosis, 429;
protective value of the skin, 429
_Ammocrypta_, _659_
_Ammodytes_, _639_, 275;
_A. lanceolatus_, 639;
_A. tobianus_, 639
Ammodytidae, _639_, 637
_Ammopleurops_, _687_
_Ammotretis_, _687_
Amniota, _145_
_Ampheristus_, _695_
_Amphioxus_, _112_ f., 4, 37, 46, 110;
general characters, 113;
external characters, 114;
anatomy, 116, 117;
musculature, 117;
skeleton, 119;
notochord, 119;
alimentary canal, 120;
branchial bars, 122;
endostyle, 123;
coelom, 123;
vascular system, 124, 125;
renal organs, 125, 127;
nervous system, 127;
sense-organs, 128;
gonads, 129;
embryology and life-history, 130, 130, 131, 132, 133, 134, 135, 136;
compared with Hemichordata, 11 f., 16, 29 f.
—see also _Branchiostoma_
Amphipnoidae, _598_
_Amphipnous_, _598_;
respiratory air-sacs of, 598;
_A. cuchia_, 294, 598
_Amphiprion_, _672_
_Amphisile_, _633_;
_A. strigata_, 633
Amphisilidae, _633_, 628
Amphistiidae, _684_, 683
_Amphistium_, _684_;
_A. paradoxum_, 684
Amphistylic, 222, 223
Anabantidae, _645_, 292, 637;
distribution of, 645
_Anabas_, _645_, 355;
_A. scandens_, 645;
labyrinthiform organ, 293
_Anableps_, _616_, 419;
intromittent organ, 414;
development of embryos in ovisacs, 418;
_A. tetrophthalmus_, 617
Anacanthini, _646_ f., 543, 702, 703
_Anacyrtus_, _575_
Anadromous, 413
Anallantoidea, _145_
Anamniota, _145_
_Anampses_, _673_
_Anapterus_, _611_
_Anarrhichas_, _709_;
teeth, 251;
_A. lupus_, 710;
eggs, 408
Anaspida, _531_ f., 149
_Anchinia_, _96_, 100;
_A. rubra_, 100;
polymorphism, 100
Anchovy, 564 {731}
_Ancylodon_, _663_
_Ancylostylus_, _549_
_Andersonia_, _588_, 589
Andrews, 113
_Anema_, _706_
Angel-Shark, 456
Angler, 718
_Anguilla_, _601_;
_A. vulgaris_ (Common Eel), 601;
larva, 602;
red glands, 307;
renal portal circulation, 319, 320
Anguillidae, _600_, 163, 405, 649 n.
_Anodonta_, _Rhodeus_ in, 584
_Anogmius_, _549_
Anomalopidae, _660_;
photophores, 178
_Anomalops_, _660_
_Anomalopterus_, _570_
_Anoplarchus_, _709_
_Anoplogaster_, _656_, 655
_Anoplopoma_, _697_, 693
_Anoplopterus_, _588_
Anostominae, _576_
_Anostomus_ (Characinidae), _576_;
(Mugilidae), _640_
Ansorge, 560
Antennariidae, _720_, 718
_Antennarius_, _720_;
nest, 414;
_A. hispidus_, scales, 191;
_A. marmoratus_, 720;
scales, 191
_Anthias_, _659_, 660
Antiarchi, _532_ f., 149
_Antigonia_, _667_
_Antimora_, _648_
_Anurella_, _78_;
development of, 78;
_A. roscovita_, larva, 78
_Apateodus_, _611_
_Apeltes_, _630_
_Aphanopus_, _679_
_Aphareus_, _660_
_Aphia_, _689_;
_A. pellucida_, 690
_Aphiocharax_, _575_
_Aphoristia_, _687_
_Aphredoderus_, _656_, 655;
_A. sayanus_, 656
_Aphyonus_, _712_, 713
_Apistus_, _695_, 692
_Aplidium_, _88_;
_A. zostericola_, stomach, 88
Apodes, _599_ f., 306
_Apodichthys_, _711_
_Apogon_, _660_
_Apolectus_, _677_
_Apostasis_, _668_
_Appendicularia_, _68_, 37;
_A. sicula_, 66
Appendicularians, 64
Appendiculariida, _65_, 66
Appendiculariidae, _68_, 38;
nervous system, 53
Appendix digitiformis, 276
_Aprion_, _660_
_Aprionodon_, _448_
_Apua_, _582_
_Aracana_, _724_
_Arapaima_, _557_;
_A. gigas_, 556, 558
Arch-centra, 196
Archaeomaenidae, _545_, 544
_Archaeomenes_, _545_
_Archaeoteuthis_, _669_
_Archaeus_, _677_
Archenteron, 20, 56, 130, 132
_Archeobatis_, _446_
Archinephric duct, 397, 398
_Arctoscopus_, _663_
Argenteum, 168
_Argentina_, _565_, 569
_Arges_, _595_
Arginae, _595_
_Argyriosus vomer_, _363_
_Argyropelecus_, _571_
_Ariscopus_, _706_
Aristotle, 36
_Arius_, _588_, 587, 589;
_A. australis_, 593;
deposition of eggs, 415;
_A. commersonii_, 593
Armed Bullhead, 700
_Arnoglossus_, _687_
_Arripis_, _663_
Arthrodira, _535_ f., 149
Arterial system, 329 f.
Artificial pearls, 167
_Ascelichthys_, _698_
_Ascidia_, _72_, 73;
structure, 39 f., 43, 45;
test, 40, 41;
body-wall, 42;
mantle, 42;
branchial cavity, 43, 48;
atrial or peribranchial cavity, 43;
other cavities of body, 44;
tentacles, 44;
endostyle, 46;
branchial sac, 47;
heart and circulation, 49, 51;
blood, 49;
neural gland, 52;
dorsal tubercle, 52;
nervous system, 53;
sense-organs, 53;
alimentary canal, 54;
renal organ, 54;
reproductive organs, 55;
embryology and life-history, 55, 57, 60;
metamorphosis, 61;
_A. challengeri_, dorsal tubercle, 79;
_A. mentula_, structure, 39 f., 40;
test, 42;
endostyle, 46;
pharynx, 47;
nervous system, 52;
larva, 78;
_A. meridionalis_, dorsal tubercle, 79;
_A. pyriformis_, dorsal tubercle, 79;
_A. translucida_, dorsal tubercle, 79;
_A. virginea_, 39 f.
Ascidiacea, _70_ f., 64
Ascidiae Compositae, _80_ f., 64;
structure, 81
Ascidiae Luciae, _90_ f., 86
Ascidiae Simplices, _71_ f.
Ascidians, 35, 64, 70
Ascidiella aspersa, 77
Ascidiidae, _72_, 64, 110
Ascidiinae, _72_
Ascidiozooids, 35, 84
Ascopera gigantea, branchial sac, 77;
dorsal tubercle, 79
_Asineops_, _656_
Aspidophora, 5 n.
_Aspidophoroides_, _700_ {732}
Aspidorhynchidae, _502_
_Aspidorhynchus_, _502_;
_A. acutirostris_, 502
_Aspius_, _582_
Aspredinidae, _596_, 575
_Aspredo_, _596_, 416
_Aspro_, _659_
_Asprotilapia_, _672_
_Asteracanthus_, _445_
Asterolepidae, _534_
_Asterolepis_, _534_
Asterospondylic, 198
_Astroblepus_, _595_
_Astronesthes_, _571_, 570, 572;
_A. niger_, photophores, 178
_Asymmetron_, _137_, 129;
distribution, 138;
_A. bassanum_, 137;
_A. caudatum_, 137, 138;
_A. cingalense_, 137;
_A. cultellum_, 137;
_A. hectori_, 137;
_A. lucayanum_, 137, 138;
_A. maldivense_, 137
Ateleaspidae, _528_
_Ateleaspis_, _528_, 530;
_A. tessellata_, 528
_Ateleopus_, _714_
_Atheresthes_, _687_, 685
_Atherina_, _639_, 640
_Atherinella_, _639_
_Atherinichthys_, 641
Atherinidae, _639_, 637
_Atherinops_, _639_
_Atherinopsis_, _639_
_Atopochilus_, _588_
Atrial cavity, 43, 44, 59, 63, 67
Atriopore, 113, 115, 117
Atrium, of Amphioxus, 113, 118, 121, 135
_Atypichthys_, _666_
_Atyposoma_, _666_
_Auchenaspis_, _529_
_Auchenipterus_, _589_;
_A. nodosus_, elastic-spring-apparatus, 358
_Auchenoglanis_, _588_
Auditory organs, 387 f., 388;
connexion with the air-bladder, 389, 390
Audouin, 37
_Aulacocephalus_, _659_
_Auliscops_, 632
_Auliscus_, _631_
_Aulolepis_, _560_
_Aulopus_, _611_
_Aulopyge_, _582_
_Aulorhamphus_, _668_
Aulorhynchidae, _631_, 628
_Aulorhynchus_, _631_, 632
_Aulostoma_, _632_;
_A. coloratum_, 632
Aulostomatidae, _632_, 628
_Aulostomatomorpha_, _570_
Autostylic, 223
_Auxis_, _678_
_Azurina_, _672_

_Badis_, _658_
_Bagarius_, _588_
_Bagrichthys_, _588_
Bagrinae, _588_
_Bagroides_, _588_
_Bagropsis_, _588_
_Bagrus_, _588_
Balanoglossus, 3, 5 f., 24, 25, 28, 30 f., 123;
embryo, 8;
history of name, 17
_Balanoglossus_, _17_, 5, 6, 13, 16;
_B. aurantiacus_, 7, 11, 15;
_B. biminiensis_, 18, 21 n.;
_B. clavigerus_, 6, 17;
_B. gigas_, 5
_Balistes_, _724_, 264, 354;
coloration, 174;
scales, 190;
sound production, 357;
_B. aculeatus_, 357;
_B. capriscus_, 724;
_B. vetula_, 361
Balistidae, _723_, 652, 721, 163
Ballowitz, 591 n.
Bancroft, 85
Band-Fish, 662
Barbels, 154
_Barbus_, _582_, 584;
_B. mosal_, 584;
_B. tropidolepis_, 583;
lower pharyngeals, 583;
_B. viviparus_, 584
_Barilius_, _582_
Barracudas, 642
Barramunda, 558
Barrois, 39
Basking Shark, 453
Bat-Fish, 720
Bateson, 5, 6, 11, 14, 20, 30 n.
_Bathyagonus_, _700_
_Bathyclupea_, _657_, 656
_Bathydraco_, _706_
_Bathygadus_, _647_
_Bathylaco_, _571_
_Bathylagus_, _566_, 565, 569
_Bathylychnus_, _571_
_Bathymaster_, _661_
_Bathymyzon_, _426_
_Bathyoncus_, _74_
_Bathyonus_, _712_
_Bathypterois_, _611_, 613;
_B. dubius_, 162, 612;
_B. longipes_, 613
_Bathysaurus_, _611_
_Bathythrissa_, _548_
_Bathytroctes_, _570_
Batoidei, _457_ f., 148
Batrachidae, _710_, 651, 704, 361;
photophores, 179
_Batrachus_, _711_;
_B. tau_, 711, 361
Baudelot, 584 n.
_Bdellostoma_, _423_;
external characters, 151;
skull, 220, 221;
pancreas, 273;
gill-sacs, 282, 423;
vascular system, 315 n.;
distribution, 423;
habits, 423;
eggs, 424;
_B. stouti_, 423;
embryo, 425
Bdellostomatidae, _423_
_Belodontichthys_, _588_
_Belone_, _638_, 411;
_B. annulata_, 638
_Belonesox_, _616_
_Belonoglanis_, _588_, 589
Belonorhynchidae, _485_, 488
_Belonostomus_, _502_ {733}
_Bembras_, _700_
_Bembrops_, _705_
Beneden, Van, 37, 39
Benham, 113
_Bentenia_, _682_
_Benthodesmus_, _679_
_Benthophilus_, _689_
_Benthosaurus_, _611_
Berycidae, _655_, 651, 652, 653, 703, 303, 361, 389
_Beryx_, _656_;
_B. affinis_ and _B. mülleri_, coloration, 165;
_B. splendens_, 655
_Betta_, _669_;
_B. pugnax_, 669
Bib, 649
_Bibronia_, _685_
_Birkenia_, _531_, 149;
_B. elegans_, 532
Birkeniidae, _531_
Bitterling, 584, 416
Black Bass, 657
Black-Fish, 610, 643
Blastocoele, 44, 49, 52, 130
Blastogenetic acceleration, 84
Blastopore, 20, 130
Blastosphere, 20, 130
Blastozooid, 84, 93
Blastula, 56
Bleak, 583, 167
_Bleekeria_, _705_
Blenniidae, _709_, 651, 702, 703, 704, 163, 271, 302, 418
_Blennius_, _709_, 710
_Blepsias_, _698_
Blind Fishes, 394, 713;
of Mammoth Cave, 619
_Blochius_, _680_
Blood, of Hemichordata, 15;
of Tunicata, 49;
of Amphioxus, 124;
of Fishes, 341
Blood-glands, 342
Blue Shark, 448
Boar-Fish, 666
Boas, 548 n.
_Bola_, _582_
_Boleophthalmus_, _689_
_Boleosoma_, _659_
_Boltenia_, _75_;
_B. pachydermatina_, _B. tuberculata_, dorsal tubercle, 79
Bolteninae, _75_
Bombay-duck, 613
Bonnet Shark, 450
Bonnier and Pérez, 95
Borgert, 99
_Bothriolepis_, _534_;
_B. canadensis_, 534
_Botia_, _582_
Botryllidae, _88_, 81, 82, 84, 110;
vessels, 42;
neural gland, 52 n.;
reproductive organs, 56;
ascidiozooid, 82
_Botrylloides_, _88_
_Botryllus_, _88_, 36, 90;
stigmata, 59;
diagram of budding, 90;
_B. schlosseri_, 80;
_B. violaceus_, 89
Bottard, 669, 696 n.
Boulenger, 459 n., 477 n., 481 n., 551 n., 584 n., 586 n., 593 n., 683 n.
_Boulengerella_, _575_
Bourne, 19
Boveri, 113, 126
_Bovichthys_, _706_
Bow-Fin, 499 = _Amia_, q.v.
_Box_, _664_, 665, 264, 276;
_B. vulgaris_, rectal caecum, 254
_Brachionichthys_, _720_
Brachiopoda, 35
_Brachychalcinus_, _575_
_Brachymystax_, _565_
_Brama_, _682_;
_B. longipinnis_, 682 n.;
_B. raii_, 682 n.
Bramidae, _682_, 676
Branchial bars, of Amphioxus, 120, 122
Branchial cavity, of Tunicata, 43, 101
Branchial clefts, 155, 277 f.
Branchial sac, 43, 44, 45, 53;
of Appendicularians, 67;
of Thaliacea, 96, 104, 105
Branchial septa, of Hemichordata, 12;
of Amphioxus, 120
_Branchiostoma_, _137_, 112, 138;
distribution, 138;
_B. belcheri_, 137, 138;
_B. californiense_, 137;
_B. capense_, 137;
_B. caribbaeum_, 137;
_B. elongatum_, 137, 138;
_B. indicum_, 137;
_B. lanceolatum_, 112, 114 n., 115, 137, 138;
transverse section, 118, 121;
nephridium, 126;
nervous system, 128, 129;
gonads, 129;
_B. nakagawae_, 137, 138;
_B. pelagicum_, 129 n., 137, 138
—see also Amphioxus
Branchiostomatidae, _137_, 112
Brauer, 571
Breathing sounds, 357
Breathing-valves, 288
_Bregmaceros_, _648_
_Breitensteinia_, _588_
_Brevoortia_, _563_
Bridge, 555, 558 n.
Bridge and Haddon, 574 n., 587 n., 590 n.
Brill, 687
Brooks, 39, 101 n., 105
_Brosmius_, _648_
_Brosmophycis_, _712_
_Brotula_, _712_, 713
_Brychaetus_, _557_
_Brycon_, _575_;
_B. fulcatus_, mouth, 577
_Bryconaethiops_, _575_
_Bryconodon_, _575_
_Bryconops_, _575_
_Bucklandium_, 589
Budding, in Pterobranchia, 24, 27;
in Tunicata, 71, 80, 81 f., 90, 97, 103
Budgett, 482, 483 n., 514, 552, 558
Bull-heads, 698
Bullhead Sharks, 444
_Bunocephalichthys_, _596_
_Bunocephalus_, _596_
Burbot, 649 {734}
Bursa Entiana, 254
Bury, 31 n.
_Butirinus_, _548_
Butter-Fish, 712, 415
_Bythitis_, _712_

_Cachius_, _582_
Cadophore, 97
Caecum cloacae, 276
_Caenotropis_, _576_
_Caesio_, _664_, 264
_Caesioperca_, _659_
_Calamichthys_, _484_, 158, 202;
distribution, 484;
_C. calabaricus_, 484
_Calamostoma_, _634_
_Callanthias_, _659_
_Callichrous_, _588_
Callichthyinae, _588_
_Callichthys_, _588_, 587, 153, 302;
intestinal respiration, 292;
_C. littoralis_, 592;
_C. paleatus_, 414, 592
_Calliodon_, _674_
Callionymidae, _706_, 704
_Callionymus_, _707_;
_C. carebares_, 707;
_C. lyra_, 707, 420 n.
_Callomystax gagata_, stridulating mechanism, 356
_Callophysus_, _588_
_Callopristodus_, _446_
_Callopterus_, 204
_Callorhynchus_, _471_;
vertebral column, 199;
frontal clasper, 223;
branchial blood-vessels, 334;
distribution, 471;
egg-case, 471;
_C. antarcticus_, 470
_Calotomus_, _674_
Campanula Halleri, 393, 394
_Campostoma_, _582_
Candiru, 593
_Canobius_, _487_
_Cantharus_, _664_
Capelin, 568
_Capoëta_, _582_
_Caprodon_, _659_
Caproidae, _666_, 653
_Capros_, _666_;
_C. aper_, 666, 357
Carangidae, _677_, 652, 676, 158, 303
_Carangodes_, _677_
_Carangopsis_, _677_
_Caranx_, _677_, 161, 284;
with Medusae, 643;
_C. hippos_, 363;
_C. rhonchus_, 363;
_C. trachurus_, 677, 307
_Carapus_, _579_
Carbonnier, 592
_Carcharias_ (_Carcharinus_), _448_;
succession of teeth, 250;
_C. glaucus_, 448;
_C. nicaraguensis_, 448
Carchariidae, _448_, 449
_Carcharinus_—see _Carcharias_
_Carcharodon rondeletii_, _451_, 452
_Careproctus_, _698_
Cariba, 578
Carp, 583, 584;
Leather-, 584
_Carpiodes_, _581_
Caryo-enteric, 102, 108
Castle, 56 n.
Cat-Fishes, 710, 587
_Cataetyx_, _712_
_Cathetostoma_, _706_
_Catla_, _582_;
_C. buchanani_, 584
_Catlocarpio_, _582_
_Catopra_, _658_
_Catoprion_, _576_
Catopteridae, _488_, 486
Catosteomi, _626_ f., 306
Catostominae, _581_
_Catostomus_, _581_
_Caturus_, _499_;
_C. furcatus_, 499;
vertebrae, 203
Caudal fin, 156, 159, 237
Caullery, 85
_Caulolatilus_, _661_
_Caulolepis_, _656_
_Caulophryne_, _719_
Cave-Fishes, 394 f., 618 f., 713
Centrarchidae, _657_, 653
_Centrarchus_, _657_
_Centrina_, _455_;
_C. salviani_, 455
Centriscidae, _633_, 628, 357
_Centriscus_, _633_, 154;
_C. scolopax_, _633_;
scales, 189, 190;
stridulation, 357
_Centrogenys_, _659_
_Centrolepis_, _487_
_Centrolophus_, _643_;
_C. britannicus_, 643;
_C. niger_, 643
_Centromochlus_, _588_, 361
_Centronotus_, _711_
_Centrophorus_, _455_
_Centropogon_, _695_
Centropominae, _660_
_Centropomus_, _660_
_Centropristes_, _659_
_Centroscyllium_, _455_
_Cephalacanthus_, _702_
Cephalaspidae, _528_
_Cephalaspis_, _529_, 149;
_C. lyelli_, 529;
_C. magnifica_, 529;
_C. murchisoni_, 528
Cephalochordata, _112_ f., 4, 38
_Cephalodiscus_, _21_ f., 5, 28, 29, 31, 32;
distribution, 23;
budding, 24;
structure, 24 f.;
males, 26;
_C. dodecalophus_, 22, 23, 24, 25
_Cepola_, _662_;
_C. rubescens_, 662
Cepolidae, _661_, 653
_Ceratias_, _719_;
phosphorescent organ, 174, 178;
_C. bispinosus_, 174
_Ceratichthys_, _582_
Ceratiidae, _719_, 718
Ceratodontidae, _507_
_Ceratodus_, _508_, 519
_Ceratoptera_, _465_;
_C. vampyrus_, 466
Ceratotrichia, 234
_Cerdale_, _709_
_Cestracion_ = _Heterodontus_, q. v.
_Cetengraulis_, _563_ {735}
Cetomimidae, _614_, 606
_Cetomimus_, _614_
_Cetopsis_, _588_, 587
Cetorhinidae, _453_
_Cetorhinus_, see _Selache_
_Chaca_, _588_;
_C. lophioides_, 589
_Chaenichthys_, _706_
_Chaenobryttus_, _657_
_Chaenopsis_, _709_
_Chaerops_, _673_
_Chaetobranchus_, _672_
_Chaetodon_, _668_
Chaetodontidae, _667_, 654, 361;
coloration, 166
_Chaetostomus_, _595_;
_C. cirrhosus_, sexual differences, 594;
_C. gigas_, 595
_Chalceus_, _575_;
_C. angulatus_, mouth, 577
_Chalcinus_, _575_
Chamisso, 36
_Champsocephalus_, _706_
_Champsodon_, _641_;
_C. vorax_, 642
Chaninae, _563_
_Channa_, _645_
_Channalabes_, _588_, 589
_Channomuraena_, _605_;
_C. vittata_, 605
_Chanoides_, _563_
_Chanos_, _563_, 563;
_C. salmoneus_, gill-helix, 294
_Characidium_, _576_
Characinidae, _575_, 574, 294;
distribution, 576;
teeth, 250;
sound production, 361;
Weberian ossicles, 389, 573
_Characodon_, _616_
_Charax_, 665
_Charitosomus_, _572_
Charr, 567
_Charybdia_, _685_
_Chascanopsetta_, _687_
_Chasmodes_, _709_
_Chatoessus_, _563_, 563
Chauliodontinae, _571_
_Chauliodus_, _571_, 570, 572
_Chaunax_, _720_
_Cheiracanthus_, _442_
_Cheirodus_, _488_;
_C. granulosus_, 488
_Cheirolepis_, _485_, 487
_Chela_, _582_
_Chelaethiops_, _582_
_Chelidoperca_, _659_
_Chelmo_, _668_
_Chelyosoma_, _73_;
_C. macleayanum_, 72
Chiaje, Delle, 17
_Chiasmodon_, _641_, 642
Chiasmodontidae, _641_, 637
_Chilinus_, _673_
_Chilio_, _673_
_Chilobranchus_, _598_
_Chilodactylus_, _664_
Chilodipterinae, _660_
_Chilodipterus_, _660_
_Chiloglanis_, _588_
_Chilorhinus_, _601_
_Chiloscyllium_, _446_, 447;
pectoral girdle, 239;
pectoral fin, 239;
pelvic girdle, 240;
pelvic fin, 240;
brain, 374
_Chimaera_, _469_, 382;
vertebral column, 199;
skull, 223;
frontal clasper, 223, 469;
gills, 282, 283;
lateral sensory organs, 386;
auditory organ, 387, 388;
distribution, 469;
egg-case, 470;
segmentation of egg, 474;
fossil, 474;
_C. affinis_, 469;
_C. colliei_, 469, 473;
_C. monstrosa_, 469;
vertebral column, 199;
skull, 223;
pectoral fin, 243;
spiral valve, 267
Chimaeridae, _468_, 474
_Chimaeropsis_, _468_
_Chimarrhichthys_, _705_
Chirocentridae, _561_, 544
_Chirocentrites_, _561_
_Chirocentrodon_, _563_
_Chirocentrus_, _562_;
vestigial spiral valve, 269;
_C. dorab_, skull and pectoral arch, 562
_Chirodon_, _575_
_Chirolophius_, _718_;
_C. naresii_, 718
_Chironemus_, _664_
_Chirostoma_, _639_
Chirothricidae, _615_, 606
_Chirothrix_, _615_;
_C. libanicus_, 615
Chlamydoselachidae, _443_
_Chlamydoselachus_, _443_, 279;
rectal gland, 276;
branchial clefts, 277;
efferent branchial vessels, 332 n.;
_C. anguineus_, 443, 444;
_C. lawleyi_, 443
_Chlamydothorax_, _17_ n.
_Chlorophthalmus_, _611_;
_C. gracilis_, 613
_Chloroscombrus_, _677_
_Chologaster_, _618_;
_C. agassizii_, 618;
_C. cornutus_, 618;
_C. papilliferus_, 618
_Chondrostachys_, _85_
Chondrostei, _485_ f., 149
Chondrosteidae, _489_, 486
_Chondrosteus_, _489_;
_C. acipenseroides_, 489, 490
_Chondrostoma_, _582_
_Chonerhinus_, _726_
Chorda-centra, 196
Chordata, characters of, _3_ f., 35, 38
_Choridactylus_, _695_, 692
_Chorimycterus_, _576_
_Chorinemus_, _677_
_Chorisochismus_, _709_
_Chorizocormus_, _89_;
_C. reticulatus_, 90
Choroid gland, 393, 394
Chromatophores, 166
Chromides, _671_
_Chrysichthys_, _588_
_Chrysophrys auratus_, 420
_Cichla_, _672_, 671
Cichlidae, _670_, 654;
distribution, 672;
eggs carried in the mouth, 416
_Cichlops_, _661_
Ciliation, of the alimentary canal, 262 {736}
_Cimolichthys_, _609_
_Ciona_, _72_;
development, 56 n.;
_C. intestinalis_, 73, 77
_Cirrhilabrus_, _673_
_Cirrhites_, _660_
_Cirrhitichthys_, _660_
Cirrhitinae, _660_;
coloration, 166
Cirri, of Amphioxus, 128
_Citharichthys dinoceros_, _685_
_Citharidium_, _576_
Citharininae, _576_
_Citharinus_, _576_, 578;
_C. geoffroyi_, 579
_Citharus_, _687_
Cladistia, _481_ f., 477
_Cladocyclus_, _561_
_Cladodus_, _438_;
_C. neilsoni_, _438_
_Cladoselache_, _438_, 148, 153, 160, 162, 197;
pectoral and pelvic girdles, 239;
pectoral and pelvic fins, 242, 245;
characters, 436 f.;
_C. fyleri_, 437
Cladoselachidae, _438_
_Clariallabes_, _588_
_Clarias_, _588_, 153, 302;
accessory respiratory organs, 293, 294;
_C. anguillaris_, 590;
_C. lazera_, 590
Clariinae, _588_
Clarke, 608
_Clarotes_, _588_
Claspers, 162, 246, 414, 432, 469, 470, 471
_Clavelina_, _71_, 83;
nervous system, 53;
stigmata, 59;
hibernation, 88;
_C. lepadiformis_, 71, 72
Clavelinidae, _71_, 81, 83, 109, 110
_Climatius_, _441_
Climbing Perch, 645, 292
Cling-Fishes, 708
_Clinus_, _709_
Cloaca, of Tunicata, 44, 45, 81, 82, 92;
of Fishes, 156, 256
Cloacal aperture, of Tunicata, 80
Cloacal cavity, of Hemimyaria, 101
Club-shaped gland, 134
_Clupea_, _563_, 564;
_C. alosa_, 564;
_C. finta_, 564;
_C. harengus_, 564, 307; = Herring (_q.v._);
_C. pilchardus_, 564;
_C. sprattus_, 564
_Clupeichthys_, _563_
Clupeidae, _562_, 544;
gill-helix, 294;
connexion of air-bladder with auditory organ, 303, 389;
eggs, 412
Clupeinae, _563_
_Cnidoglanis_, _588_
Coal-Fish, 649
Cobitidinae, _582_, 585
_Cobitis_, _582_, 271;
_C. taenia_, 358
_Cobitopsis_, _639_;
_C. acuta_, 639
_Coccodus_, _498_
_Coccolepis_, _487_
_Coccosteus_, _535_, 149, 536;
_C. decipiens_, 535, 536
_Cochliodon_, _595_
Cochliodontidae, _445_;
teeth, 251
_Cochliodus_, _445_
_Cochlognathus_, _582_
Cod, 648, 648; = _Gadus morrhua_, q.v.
Coelacanthidae, _480_, 481
_Coelacanthus_, _481_, 160
Coelocormidae, _86_
_Coelocormus huxleyi_, _86_;
reproductive organs, 56
Coelolepidae, _524_, 530
Coelom (body-cavity), in Hemichordata, 8, 21, 24 f.;
in Tunicata, 44;
in Amphioxus, 123, 132 f.;
in Fishes, 397
_Coelonotus_, _634_, 635
_Coelophrys_, _720_
Coffer-Fishes, 152, 361
_Coilia_, _563_, 563
Cole, 25 n.
Cole and Johnstone, 687 n.
_Colella_, _85_, 83;
_C. pedunculata_, 85;
_C. quoyi_, 80
Collar-pore, 9, 25, 27
Collett, 714 n.
_Coloconger_, _601_
_Colocopus_, _668_
Colour, of Fishes, 164 f.;
brilliancy and variety, 164;
cause of, 166;
changes, 169;
protective value, 171;
aggressive and alluring, 173;
warning, 174
_Columbia_, _621_;
_C. transmontana_, 621
Comephoridae, _696_, 692, 694, 418
_Comephorus_, _697_, 692 n.
Compound Ascidians, 35, 36 f., 70, 71, 80 f., 110;
eggs, 56
_Conchopoma_, _507_
_Conger_, _601_;
_C. vulgaris_, skull and pectoral arch, 600
Congrogadidae, _713_, 704
_Congrogadus_, _713_
_Congromuraena_, _601_
_Conocara_, _570_
_Conorhynchus_, _588_
Conte and Vaney, 27 n.
Cope, 477 n., 542, 543, 573, 619, 626
_Copidoglanis_, _588_
_Copodus_, _446_
Coprolites, 268
_Coregonus_, _565_, 568, 311;
_C. clupeoides_, 568;
_C. lavaretus_, 568;
_C. oxyrhynchus_, 568;
_C. pollan_, 568;
_C. vandesius_, 568
_Corella_, _73_;
stigmata, 48;
_C. japonica_, branchial sac, 73;
_C. parallelogramma_, 73
Corellinae, _73_
_Coreoperca_, _659_
_Coridodax_, _674_
_Coris_, _673_
_Corvina_, _663_;
_C. lobata_, air-bladder, 304
_Corydoras_, _588_;
_C. paleatus_, 592
_Corynascidia_, _73_;
_C. suhmi_, 72;
branchial sac, 73
_Corynopoma_, _575_ {737}
_Coryphaena_, _681_
Coryphaenidae, _681_, 676
_Coryphaenoides_, _647_
_Cossyphus_, _673_
Costa, 112
Coste, 630 n.
Cottidae, _697_, 692, 694
_Cottocomephorus_, _697_, 692 n.
_Cottunculus_, _698_
_Cottus_, _698_;
_C. bubalis_, 698;
_C. gobio_, 698;
_C. scorpius_, 698, 357
_Cotylis_, _709_
Cranial nerves, 378, 380
Craniata, _4_, 38;
characters of, 141;
classification, 145
_Cranoglanis_, _588_
_Creagrutus_, _575_
_Crenicichla_, _672_
_Crenidens_, _665_
_Crenuchus_, _575_
_Crepidogaster_, _709_
Crista acustica, 60
_Cromeria_, _573_
Cromeriidae, _573_, 545
_Cromileptes_, _659_
Crossognathidae, _565_
_Crossognathus_, _565_
_Crossopholis_, _492_
Crossopterygii, _476_ f., 149;
distribution, 483
_Crossorhinus_, _447_
_Cryodraco_, _706_
_Cryphiolepis_, _487_
_Cryptopterus_, _588_
_Cryptotomus_, _674_
_Crystallaria_, _659_
_Crystallogobius_, _689_
_Ctenochaetus_, _668_
_Ctenodentex_, _665_
Ctenodontidae, _505_
_Ctenodus_, _506_
_Ctenolabrus_, _673_
_Ctenolates_, _659_
_Ctenothrissa_, _560_;
_C. vexillifer_, 559
Ctenothrissidae, _559_, 544
_Cubiceps_, _643_
Cuchia, 598, 294
Cuénot, 584 n.
_Culeolus_, _75_;
spicules, 87;
_C. murrayi_, 42;
_C. moseleyi_, dorsal tubercle, 79;
_C. wyville-thomsoni_, 75
_Culter_, _582_
Cunningham, 565 n., 602 n., 687 n.
_Curimatus_, _576_
Cutaneous sense-organs, of Fishes, 383 f., 385, 386
Cuvier, 36
_Cyathaspis_, _527_
Cyathozooid, 91, 93, 94
_Cybium_, _678_
_Cyclobatis_, _462_
Cyclomyaria, _95_, 101
_Cyclopterichthys_, _698_
Cyclopteridae, _698_, 692, 694, 302
_Cyclopterus_, _698_, 321, 408, 415;
sucker, 162;
_C. lumpus_, 699;
rectal valve, 254
_Cyclosalpa_, _108_;
_C. pinnata_, 102, 108
Cyclospondylic, 198
Cyclostomata, _421_ f., 145 f.;
characters, 146;
external features, 150;
skeleton, 197 f.;
teeth, alimentary canal and digestive glands, 247 f.;
respiratory organs, 279 f.;
vascular system, 315 f.;
blood-glands, 343;
nervous system, 367 f.;
organs of special sense, 383 f.;
kidneys and reproductive organs, 399 f.
_Cyclothone_, _571_
_Cymatogaster_, _670_
_Cynoglossus_, _687_;
_C. lingua_, 686;
_C. semilaevis_, 393
_Cynolebias_, _616_
_Cynthia_, _75_;
branchial sac, 74;
_C. cerebriformis_, dorsal tubercle, 79;
_C. formosa_, 76;
dorsal tubercle, 79;
_C. papietensis_, dorsal tubercle, 79
Cynthiidae, _74_, 64, 110;
branchial sac, 48;
neural gland, 52 n.;
reproductive organs, 55;
eggs, 56;
dorsal tubercle, 79
Cynthiinae, _75_;
tentacles, 75
Cyphosidae, _657_, 653
_Cyphosus_, _657_
Cyprinidae, _581_, 575, 271;
ventral suckers, 162;
absence of jaw-teeth, 251;
air-bladder, 302;
breathing sounds, 358;
connexion of auditory organ with air-bladder, 389
Cyprininae, _582_, 583
_Cyprinion_, _582_
_Cyprinodon_, _616_
Cyprinodontidae, _616_, 606, 163, 275, 414, 418;
distribution, 617
_Cyprinus_, _582_, 155;
pharyngeal teeth, 252;
_C. auratus_, eyes, 155;
coloration, 171;
_C. carassius_, 585;
_C. carpio_, 583, 307, 358
Cystoarian, 403
_Cystodytes_, _85_;
spicules, 87
_Cyttoides_, _683_
_Cyttopsis_, _683_
_Cyttus_, _683_

Dab, 687;
Long Rough, 687;
Smear, 687
_Dactylopogon_, _611_
Dactylopteridae, _701_, 694, 361
_Dactylopterus_, _701_, 693;
_D. volitans_, 161, 355, 357, 361, 399, 701;
pectoral arch, 693
_Dallia_, _610_;
_D. pectoralis_, 610, 611
Dalliidae, _610_, 606
_Danio_, _582_
_Dapedius_, _498_, _541_ n.;
_D. politus_, 498
_Dapedoglossus_, _557_;
_D. testis_, 556
Dareste, 721 {738}
Darters, 659
_Dascyllus_, _672_
_Dasyatis sabina_, _464_
_Dasyscopelus_, _611_
_Datnioides_, _658_
Dawydoff, 16 n.
Day, 569 n., 593 n.
Deal-Fish, 715
Delhez, 551
_Deltodus_, _445_
_Deltoptychius_, _445_
Demersal, 408
_Dendrodoa_, _76_
_Dentex_, _664_
Dentition, 247 f.;
dentinal tissues, 249;
fixation of teeth, 249;
succession and replacement, 250;
shape, 251;
sexual differences, 251;
pharyngeal teeth, 251;
Cyclostomata, 247;
_Petromyzon_, 248;
Fishes, 248 f.;
_Scyllium_, 249;
_Carcharias_, 250
Dercetidae, _623_, 622
_Dercetis_, _623_
_Derepodichthys_, _712_
_Derichthys_, _601_
Dermal denticles, 183 f.;
structure and development, 183, 184, 185
_Diagramma_, _664_
_Dibranchus_, _720_
_Dicerobatis_, _465_
_Dicrotus_, _679_
Didemnidae, _86_, 82, 110
_Didemnum_, _87_
_Didymaspis_, _530_
_Dinichthys_, _537_, 149
_Dinolestes_, _659_
_Dinoperca_, _659_
_Diodon_, _726_, 163, 354, 361;
scales, 191;
teeth, 251;
_D. geometricus_, 726;
_D. hystrix_, 364
Diodontidae, _726_, 722
Diphycercal, 159
Diplacanthidae, _441_
_Diplacanthopoma_, _712_, 713
_Diplacanthus_, _441_
_Diplesium_, _659_
_Diplocrepis_, _709_
_Diplomystes_, _588_, 587
_Diplomystus_, _563_
_Diplophos_, _571_
_Diplophysa_, _582_
_Diplopterus_, _477_
_Diplosoma_, _87_;
section, 87
Diplosomatidae, _87_, 110
_Diplosomoides lacazii_, larva, 78
Diplospondylic, 198
_Diplurus_, _481_, 161
Dipneusti—see Dipnoi
Dipnoi (Dipneusti), _505_ f., 149;
distribution, 512
_Dipterodon_, _665_
_Dipterus_, _506_, 519;
_D. valenciennesi_, 506
_Diptychus_, _582_
Disartete, 636 n.
Discocephali, _691_ f., 651, 652
_Discognathus_, _582_
_Discopyge_, _464_
_Distaplia_, _85_;
_D. magnilarva_, larva, 78
Distichodontinae, _576_
_Distichodus_, _576_;
_D. niloticus_, mouth, 577
_Distoma_, _85_
Distomatidae, _85_, 81, 82, 83, 86, 110;
reproductive organs, 56;
ascidiozooid, 82;
transverse section, 86
_Ditrema_, _670_;
_D. temminckii_, 670
Dog-Fishes, _446_
_Dolchinia_, _96_, 100;
_D. mirabilis_, 100
_Dolichoglossus_, _17_, 5, 13;
_D. kowalevskii_, 6, 7, 9, 20;
_D. otagoensis_, 11
_Dolichorhynchus_, _137_;
_D. indicus_, 137
Doliolidae, _96_, 39, 110
_Doliolum_, _96_, 37;
structure, 96;
life-history, 97, 98;
occurrence, 99;
budding, 97;
polymorphism, 98;
_D. nationalis_, 99;
_D. tritonis_, 96, 99
Dollo, 518
_Dolopichthys_, _719_
Dolphins, 681
Doradinae, _588_
Dorado, 578
_Doras_, _588_, 590, 592, 363;
intestinal respiration, 292;
stridulation, 357;
elastic-spring-apparatus, 359;
_D. maculatus_, air-bladder, 303;
nature of sounds, 362
Dorsal lamina, 45, 47, 52, 101, 105
Dorsal pore, 18, 19, 31
Dorsal tubercle, 52, 79
_Doryichthys_, _634_, 635
_Doumea_, _588_
_Doydixodon_, _664_
_Draconetta_, _706_
Dragonet, 707
Drasche, 38
Drepanaspidae, _525_, 530
_Drepanaspis gemündenensis_, _526_, 530, 525, 526
_Drepane_, _668_
Drepanidae, _668_, 654
Drum, 663, 304, 362
_Ductor_, _677_
Dufosse, 355
_Dussumieria_, _563_, 563
Dybowski, 697 n.
_Dysichthys_, _596_
_Dysomma_, _603_
_Dysommatopsis_, _603_

Eagle Rays, _465_
Echeneididae, _691_
_Echeneis_, _691_;
cephalic sucker, 161
_Echidna_, _605_ {739}
_Echidnocephalus_, _624_
_Echinorhinus_, _455_;
_E. spinosus_, 456
_Echiostoma_, _571_
_Ecteinascidia_, _71_
_Edaphodon_, _474_
Edinger, 271
Eels, 599 f., 601 f., 163, 405
Eel-Fares, 602
_Egertonia_, _674_
Eggs, of Hemichordata, 20, 26;
of Tunicata, 55, 73, 84, 97, 106;
of Amphioxus, 130;
of Fishes, 408 f., 423, 424, 428, 432, 433, 435, 456, 470, 471, 494,
504, 510;
alecithal and telolecithal, 410;
holoblastic and meroblastic segmentation, 409, 410;
micropyles, 411, 412;
deposition, 411;
attachment, 411, 424, 433, 434;
demersal and pelagic, 411, 412;
spawning, 412;
relative fecundity, 412;
fertilisation, 413;
sexual relations, 413;
sexual congress, 414, 427, 428, 432;
time of hatching, 417, 433, 494, 500, 504;
influence of temperature, 417;
of _Aspredo_, 596;
of _Batrachus tau_, 711
Ehrenbaum, 685 n.
Eigenmann, 602 n., 619 n., 670 n.
_Eigenmannia_, _579_
_Elacate_, _678_
Elaeoblast, 107, 107
Elasmobranchii, _431_ f., 148
_Elasmodus_, _474_
_Elassoma_, _657_
Electric, Cat-Fish, 591;
Eel, 580, 365 f.;
Rays, 462;
Mormyridae, 550;
organs, 365 f.
_Eleginops_, _706_
_Eleotris_, _689_;
_E. marmorata_, 689
_Ellipesurus_, _465_
_Elonichthys_, _487_
Elopidae, _546_, 544
_Elopopsis_, _547_
_Elops_, _547_;
_E. lacerta_, 547;
_E. saurus_, 547
Elvers, 602
_Embiotoca_, _670_
Embiotocidae, _670_, 654, 418, 419
_Embolichthys_, _705_
Embryology (development), of Hemichordata, 18;
of Tunicata, 55;
of Amphioxus, 130;
of Fishes, 417
Embryonic nutrition;
food-yolk, 409, 417;
ovarian secretion, 419;
oviducal or uterine secretion, 434, 435;
placentas, 98, 101, 107, 434
Emery, 622, 623, 685 n., 714 n.
_Emmnion_, _709_
_Empetrichthys_, _616_
_Encheliophis_, _625_;
_E. vermicularis_, 625
_Enchelycore_, _605_
Enchodontidae, _608_, 606
_Enchodus_, _609_
End-buds, 383
Endostyle, 46, 53, 58, 67;
of Amphioxus, 122
Engraulinae, _563_
_Engraulis_, _563_;
_E. encrasicholus_, 564
_Enneanectes_, _709_
Entero-epicardiac budding, 82
Enteropneusta, _5_ f., 30 n.;
distribution, 5, 6;
coloration, 7;
habitat, 6, 7;
divisions of body, 7;
burrowing, 7;
body-cavities, 8;
body-wall, 9;
nervous system, 9;
alimentary canal, 11;
vascular system, 15;
excretion, 15;
reproductive organs, 16;
regeneration, 16;
development, 18 f.
_Entersphenus_, _426_
_Eocottus_, _698_
_Eothynnus_, _678_
_Epapterus_, _589_
_Ephippion_, _726_
_Ephippus_, _668_;
_E. faber_, 668
_Epibulus_, _673_
Epicardiac budding, 81
Epicardium, 44, 60, 71, 83
_Epigonus_, _659_
_Epinephelus_, _659_, 660
_Epinnula_, _679_
Epipharyngeal groove, 123
_Eques_, _663_
_Equula_, _663_
_Eremophilus_, _589_
_Eretmodus_, _672_
_Ereunias_, _698_
Erythrininae, _575_
_Erythrinus_, _575_, 578;
air-bladder, 305, 306;
_E. taeniatus_, _E. braziliensis_, air-bladder as a respiratory organ,
291
Esocidae, _609_, 606, 275;
distribution, 610
_Esox_, _609_;
teeth, 250, 262;
_E. lucius_, 609, 307;
skeleton, 609;
_E. nobilior_, 609;
_E. lepidotus_, 610
Essence orientale, 585
_Esunculus_, _548_
_Etelis_, _660_
_Etheostoma_, _659_
_Etroplus_, _672_
_Etrumeus_, _563_
_Euanemus_, 359
_Eucalia_, _630_
_Euchilichthys_, _588_, 587
_Eucirrhichthys_, _582_
_Eugnathichthys_, _576_
Eugnathidae, _498_, 497
_Eugnathus_, _499_
_Eugyra_, _77_, 78;
_E. glutinans_, 79;
_E. kerguelenensis_, branchial sac, 77
_Eukeraspis pustulifera_, 529
_Eumeda_, _588_
_Euoxymetopon_, _679_
_Euphanerops_, _532_
_Eupleurogrammus_, _679
Eurycormus_, _499_; {740}
_E. speciosus_, vertebrae, 203
_Eurynotus_, _487_, 488;
_E. crenatus_, 487
_Eurypharynx_, _604_
_Eurypholis_, _609_
_Eusthenopteron_, _478_, 202, 246;
_E. foordi_, 479
_Euthacanthus_, _441_
_Euthynotus_, 204
_Eutropiichthys_, _587_
_Eutropius_, _588_
_Exocoetoides_, _615_
_Exocoetus_, _638_, 161, 173, 353, 411
_Exoglossum_, _582_
_Exostoma_, _588_, 586, 587
External characters, Cyclostomata, 150 f.;
Fishes, 152 f.
Eycleshymer, 592 n.
Eye, 155, 393, 394, 395;
degeneration in deep-sea and cave Fishes, 394;
telescopic, 395
Eyelids, 395

Facciola, 685 n.
Fatio, 569 n.
Felchen, 568
_Fierasfer_, _625_, 622, 399;
_F. acus_, 156, 626
Fierasferidae, _625_, 623
File-Fishes, 724
Filippi, 690 n.
Fins, of Fishes, 156;
median, 156;
paired, 157;
pectoral, 157;
lobate, 157;
pelvic, 158;
caudal, 159;
modified to form suckers, 161;
degeneration and atrophy, 162;
endoskeletal elements, 234, 235, 236, 237, 239, 240, 241, 242, 243,
244, 245, 246;
exoskeletal elements, 158, 234, 236
Fin-rays, of Amphioxus, 120;
of Fishes, 158, 234, 236
Fishes, 141 f.;
systematic position and classification, 141;
external features, 152;
coloration, 164;
poison glands, 176;
phosphorescent organs, 178;
skin and scales, 182;
skeleton, 193;
dentition, alimentary canal, and digestive glands, 247;
respiratory organs, 277;
air-bladder, 297;
vascular system, lymphatics, and blood-glands, 313;
muscular system, locomotion, sound-producing organs, and electric
organs, 349;
nervous system and organs of special sense, 367;
kidneys and reproductive organs, breeding, 397;
systematic, 431 f.
Fishing-Frog, 718
_Fistularia_, _632_, 154;
_F. tabaccaria_, 632
Fistulariidae, _632_, 628
Flat-Fishes, 685
Flounder, 687;
coloration, 167, 170
Flute-mouths, 154
Flying-Fish, 638, 161, 173, 353, 411;
fresh-water, 559
Flying Gurnards, 701, 355, 361
Fol, 38
_Forbesella_, _75_;
_F. tessellata_, 76;
dorsal tubercle, 79
Forskål, 36
Fowler, 23
Frilled Sharks, 443
_Fritillaria_, _69_, 70;
_F. furcata_, 70;
_F. megachile_, 66
Fritsch, 551, 591 n.
Frost-Fish, 679
_Fundulus_, _616_

Gadidae, _647_, 702, 158, 303, 307, 361, 389, 412;
photophores, 179
_Gadomus_, _647_
_Gadopsis_, _709_
Gadow, 193 n.
_Gadus_, _648_, 168;
_G. aeglefinus_, 649, 308, 361;
_G. luscus_, 649;
_G. merlangus_, 649;
coloration, 168;
pyloric caeca, 275;
_G. morrhua_, 648, 648;
vertebrae, 205;
skull, 230;
pseudobranch, 284;
air-bladder, 303;
red gland, 307, 308;
vascular system, 320, 323, 336, 337;
spleen, 343;
sounds, 361;
_G. pollachius_, 649;
_G. virens_, 649;
sensory canals, 386;
tail, 646
_Gagata_, _588_
_Galaxias_, _607_, 608;
_G. attenuatus_, 607, 608;
_G. brevipinnis_, 607
Galaxiidae, _607_, 606, 163, 405;
distribution, 607
_Galeichthys_, _588_, 587, 593
_Galeocerdo_, _448_;
_G. arcticus_, 448;
_G. tigrinus_, 448
_Galeoides_, _641_
_Galeus_, _449_, 298;
_G. canis_, 449
_Gambusia_, _616_;
development of embryos in ovisacs, 418
_Ganodus_, _474_
Ganoidei, _149_
Gar-Fish, 411 (_Belone_)
Gar-Pike, 638 (_Belone_);
503 (_Lepidosteus_)—see also _Lepidosteus_
Garman, 616 n., 619, 698 n.
Gastric glands, 270
_Gastrochisma_, _678_
_Gastromyzon_, _582_;
_G. borneensis_, 586;
sucker, 162
_Gastropelecus_, _575_
Gastrosteidae, _629_, 627;
distribution, 631
_Gastrosteus_, _630_, 163, 169, 271, 288;
_G. aculeatus_, 357, 630;
pectoral arch of, 630;
_G. pungitius_, 630;
_G. spinosus_, 354;
_G. texanus_, 631 n.
_Gastrostomus_, _604_
_Gastrotoceus_, _634_, 635
Gastrula, 20, 56, 130, 131
_Gavialiceps_, _603_ {741}
_Gazza_, _663_
Gegenbaur, 5 n., 37, 570 n.
_Gempylus_, _679_
_Genidens_, _588_
Genital pores, 403
Genital wings, of Enteropneusta, 16, 10
_Genyomyrus_, _551_, 549
_Genypterus_, _713_
Geoffroy, 677 n.
_Geophagus_, _672_
_Geotria_, _426_
_Gephyroberyx_, _656_
Gephyrocercal, 161
_Gephyroglanis_, _588_
Gerbe, 673 n.
_Gerlachia_, _706_
_Gerres_, _663_
Gerridae, _663_, 654
Giard, 38, 39
Gigantactinidae, _720_, 718
_Gigantactis vanhoeffeni_, _720_
Gilbert, 548
_Gilbertia_, _659_
Gilchrist, 571
Gill, of _Salpa_, 105
Gill, T., 542, 570 n., 599 n., 629
Gill-helix, 294
Gill-slits, 4;
of Enteropneusta, 11, 12, 20, 30;
of Pterobranchia, 25, 27;
of Tunicata, 47, 67, 105;
of Amphioxus, 120;
of Fishes, 155, 277 f.
Gillaroo Trout, 260
Gills—see Respiratory organs
_Ginglymostoma_, _447_
_Girardinus_, _616_;
sexual congress, 414
_Girella_, _664_
_Glandiceps_, _17_, 5, 6, 13, 14, 15;
_G. abyssicola_, 6;
_G. hacksi_, 6;
_G. talaboti_, 5
Glandicipitidae, _17_
Glandula pterygopodia, 182
_Glanidium_, _588_
_Glaniopsis_, _582_
_Glaucosoma_, _660_
Globe-Fishes, 726, 152, 163
Glomerulus, of Enteropneusta, 15;
of Fishes, 398, 399
Glomus, 398
_Glossobalanus_, _17_, 5, 13;
_G. minutus_, 10, 11;
_G. ruficollis_, 17 n.;
_G. sarniensis_, 5, 10
_Glossodus_, _446_
_Glyphidodon_, _672_
_Glyptocephalus_, _687_;
_G. cynoglossus_, 687;
_G. microcephalus_, 687
_Glyptolepis_, _480_
_Glyptopomus_, _477_
_Glyptosternum_, _588_
_Gnathacanthus_, _695_
_Gnathonemus_, _551_, 549;
_G. curvirostris_, 550;
_G. numenius_, 550
Gnathostomata, _145_;
characters of, 147
Gobiesocidae, _707_, 704
_Gobiesox_, _709_
Gobiidae, _689_
Gobiiformes, _688_ f., 651, 652
_Gobio_, _582_
_Gobiodon_, _689_
_Gobiosoma_, _689_
_Gobius_, _689_, 690;
_G. minutus_, care of eggs, 415;
_G. ruthensparri_, 689
Gold-Fish, 585, 155, 171
_Gomphosus_, _673_
Gonads (reproductive organs), of Hemichordata, 16, 25;
of Tunicata, 55, 67, 76, 93, 97, 105;
of Amphioxus, 129;
of Fishes, 402 f., 400, 403
Gonoducts, of Fishes, 404 f.;
Elasmobranchs, 400, 404;
Teleostei, 400, 404, 406;
Holocephali, 405;
Dipnoi, 405, 406, 407;
Crossopterygii, 405;
Chondrostei, 405;
Holostei, 405
Gonorhynchidae, _572_, 545
_Gonorhynchus greyi_, _572_, 572
_Gonostoma_, _571_
Gonostomatinae, _571_
Gonozooid, 99, 100
Goode, Brown, 680 n., 710, 725
Goode and Bean, 614 n.
Goodrich, 29, 113, 126
_Goodsiria_, _89_;
_G. placenta_, 89
Gourami, 669
_Grammicolepis_, _683_
_Grammistes_, _660_
Grammistinae, _660_
Grassi, 21 n.
Grassi and Calandruccio, 602
Grayling, 568
Greene, 711 n.
Greenland Shark, 455
Gressin, 705 n.
Grey Mullets, 640
Grobben, 39
Groove of Hatschek, 128
Guanin, 167
Guaninkalk, 167 n.
Guitel, 690 n., 709 n., 710
Gunnel, 712
Günther, 543, 557, 569 n., 621 n. 632, 674, 711 n., 719
Gurnards, 701—see also _Trigla_
Gwyniad, 568
_Gymnallabes_, _588_
_Gymnapistus_, _695_
Gymnarchinae, _551_
_Gymnarchus_, _551_;
larval gills, 290, 418, 419;
abdominal pores, 401;
size of eggs, 408;
_G. niloticus_, 552;
embryo, 419
_Gymnelis_, _712_
Gymnoarian, 403
_Gymnocypris_, _582_
Gymnodontes, _725_ f., 721, 272, 361
_Gymnodraco_, _706_ {742}
Gymnotidae, _579_, 574, 163, 256, 302, 389
_Gymnotus_, _579_, 581, 649 n.;
electric organs, 365, 366;
_G. electricus_, 580
_Gyrinochilus_, _582_
_Gyrodus_, _498_
_Gyrolepis_, _487_
_Gyroptychius_, _479_
_Gyrosteus_, _489_

Haddock, 649, 308, 361
Haddon, 289
_Haemulon_, _664_
Hag-Fishes, 421
Hake, 649, 308
Haldeman, 19 n.
_Halec_, _609_
Half-Beak, 154, 414
Halibut, 687
_Halicmethes_, _720_
_Halieutaea_, _720_
_Halilophus mirabilis_, _21_
_Halimochirurgus_, _723_
_Haloporphyrus_, _648_
_Halosaurichthys_, _624_
Halosauridae, _623_;
photophores, 178
_Halosauropsis_, _624_;
_H. macrochir_, 621 n., 624
_Halosaurus_, _624_
Hammer-head Sharks, 449
Hancock, 53, 591 n., 592
Haplistia, _477_ n.
_Haplochilus_, _616_
_Haplochiton_, _608_
Haplochitonidae, _608_, 606
Haplodactylidae, _664_, 650, 654
_Haplodactylus_, _664_
Haplomi, _605_ f., 651, 306
_Haplonotus_, _663_
Harmout, 590
_Harpagifer_, _706_
_Harpodon_, _611_;
_H. nehereus_, 613;
_H. squamosus_, 613
_Harrimania_, _17_, 5;
_H. kupfferi_, 20 n.
Harrimaniidae, _17_
_Harriotta_, _471_, 154, 223;
distribution, 473;
_H. raleighana_, 472;
young, 473
Hartmeyer, 38
Hasselt, van, 36
Hatching, of eggs, 417
Hatschek, 113;
grove of, 128
Haus, of Appendicularians, 66
Head, shape and relative size, 153
Heart, of Tunicata, 49, 67;
of Fishes, 327, 328
Heart-vesicle, of Hemichordata, 15
Heincke, 565 n.
_Helgia_, _582_
_Heliastes_, _672_
_Helicophagus_, _588_
Heller, 38
_Helodus_, _445_
_Helogenes_, _589_
_Helostoma_, _669_
_Hemerocoetes_, _706_
Hemibranch, 278
Hemibranchii, _627_, 629
Hemichordata, _4_ f., 3, 38;
affinities, 30 f.
_Hemichromis_, _671_
_Hemiexocoetus_, _638_
Hemimyaria, _101_ f., 95, 96
Hemiodontinae, _576_
_Hemiodus_, _576_
_Hemipimelodus_, _588_
_Hemirhamphus_, _638_;
beak, 154;
intromittent organ, 414
_Hemirhynchus_, _680_
_Hemisilurus_, _588_
_Hemithyrsites_, _679_
_Hemitripterus_, 698
Hemprich and Ehrenberg, 558 n.
_Heniochus_, _668_
_Henoplosus_, _666_
Hensel, 593 n.
_Hephthocara_, _712_, 713
_Heptanchus_, _443_;
branchial clefts, 277;
_H. cinereus_, 443;
skull, 222
_Heptapterus_, _588_
Herdman, 38, 108 n., 109 n.
Hermaphrodite Fishes, 420
Hermaphroditism, 420
_Hermosilla_, _657_
_Heros_, _672_
Herring, 564, 389;
coloration, 173;
gonads, 403;
eggs, 412;
influence of temperature on time of hatching, 417
_Heterobranchus_, _588_, 590;
accessory gill, 293
_Heterochaerops_, _673_
_Heteroconger_, _601_
Heterodont, 251
Heterodontidae, _444_;
teeth, 251;
persistent nephrostomes, 401, 445
_Heterodontus_, _444_;
skull, 223;
teeth, 251;
spiral valve, 267;
_H. philippi_, 445
Heteromi, _621_ f., 306
_Heteropleuron_, _137_, 138;
_H. bassanum_, 137;
_H. cingalense_, 137;
_H. cultellum_, 137;
_H. hectori_, 137;
_H. maldivense_, 137
_Heterostichus_, _709_
Heterostraci, _524_ f., 149
_Heterothrissa_, _563_
_Heterotis_, _557_, 555;
larval gills, 290, 418;
size of eggs, 408;
_H. ehrenbergii_, gill-helix, 294;
_H. niloticus_, 556, 558
Hexagrammidae, _696_, 694
_Hexagrammus_, _696_
_Hexanchus_, _443_;
branchial clefts, 277;
_H. griseus_, 443
Hickson, 289, 690 n.
_Hierichthys_, _713_ {743}
_Himantolophus_, _719_;
_H. reinhardti_, 719
Hincks, 23 n.
_Hippocampus_, _634_, 635, 154, 156, 283;
prehensile tail, 163;
_H. brevirostris_, 361, 362;
_H. guttulatus_, 635
_Hippoglossina_, _687_
_Hippoglossoides_, _687_;
_H. limandoides_, 687
_Hippoglossus_, _687_;
_H. vulgaris_, 687
_Histiocephalus_, _695_
Histiophoridae, _679_, 676
_Histiophorus_, _680_
_Histiopterus_, _660_
_Histiothrissa_, _563_
Hjort, 39, 83
_Holacanthus_, _668_, 361
_Holargyreus_, _648_
_Holaspis_, _527_
Holmwood, 692 n.
Holoblastic, 97, 409, 410
Holobranch, 278
_Holocentrum_, _656_, 655;
_H. sogho_, 361
Holocephali, _466_ f., 148
Holoptychidae, _479_, 202
_Holoptychius_, _480_;
_H. leptopterus_, 236;
_H. flemingi_, 479
Holosomata, _88_ f., 81, 82, 110
Holostei, _495_ f., 149, 497
Holothurians, _Fierasfer_ in, 626;
_Syngnathus_ and _Doryichthys_ in, 635
_Holoxenus_, _695_;
_H. cutaneus_, coloration, 165
Holt, 690 n., 707
_Homaloptera_, _582_
Homalopterinae, _582_, 585
Homocercal, 160, 237
_Homosoma_, _643_
_Homosteus_, _536_
Hoplichthyidae, _699_, 694
_Hoplichthys_, _700_
Hoplognathidae, _662_, 653
_Hoplognathus_, _662_
_Hoplopagrus_, _660_
_Hoplopteryx_, _656_;
_H. lewesiensis_, 656
Horse-Mackerel, 677, 158
Houting, 568
Humboldt, 581, 595
Hundsfisch, 610
Huot, 627
Huxley, 30 n., 37, 112
_Hybodus_, _445_;
vertebral column, _197_
_Hydrocyon_, _575_;
_H. goliath_, 578
Hydrocyoninae, _575_
_Hydrolagus colliei_, _469_
_Hygrogonus_, _672_
_Hymenocephalus_, _647_
_Hyodon_, _553_;
_H. alosoides_, skull and pectoral arch, 553
Hyodontidae, _552_, 544, 389, 405
Hyostylic, 222
_Hyperlophus_, _563_
_Hyperopisus_, _549_;
_H. bebe_, 552
Hyperpharyngeal groove, 123
_Hypnos_, _464_;
electric organs, 365;
_H. subnigrum_, 258
Hypobranchial groove, 46
Hypobythiinae, _72_
_Hypobythius_, _72_;
_H. calycodes_, 72, 72;
_H. moseleyi_, _72_
_Hypomesus_, _566_
Hypopharyngeal groove, 122, 123
_Hypophthalmichthys_, _582_;
_H. molitrix_, 584
Hypophthalminae, _589_
_Hypophthalmus_, _589_
Hypophysial canal, 58
Hypophysis, 129, 370
_Hypoprion_, _448_
_Hypoptopoma_, _595_
_Hypoptychus_, _639_
_Hypostoma_—see _Plecostomus_
Hypostomides, _628_
_Hypsocormus_, _501_;
_H. insignis_, 502
Hyrtl, 558 n., 599 n.
_Hysterocarpus_, _670_

_Iasis_, _108_;
_I. cordiformis-zonaria_, 108
_Icelus_, _698_
Ichthyoborinae, _576_
_Ichthyoborus_, _576_
_Ichthyocampus_, _634_
_Ichthyococcus_, _571_
_Ichthyodectes_, _561_
Ichthyodorulites, 159, 435, 446, 467
_Ichthyomyzon_, _426_
Ichthyopsida, _145_
Ichthyotomi, _438_ f., 148
_Icichthys_, _644_
Icosteidae, _644_, 637
_Icosteus_, _644_;
_I. enigmaticus_, 644
_Iguanodectes_, _575_
Ihering, 593 n.
Ikeda, 29
_Ilyophis_, _601_
Infundibular organ, 127
Inter-renal bodies, 346, 346
Intromittent organs, 414
_Ipnops_, _611_, 613;
_I. murrayi_, 612;
photophore, 179
Iridocytes, 166
_Ischnacanthus_, _441_
_Ischyodus_, _474_
_Isichthys_, _551_
_Iso_, _639_
Isospondyli, _543_, 620
_Istieus_, _549_
_Isurichthys_, _678_

Jacoby, 601, 602 n.
_Janessa_, _446_
_Jenynsia_, _616_
Jobert, 593 n.
John Dory, 683, 308, 361, 363
Jones, 720 n. {744}
Jordan, 542
Jordan and Evermann, 569 n., 620
Jordan and Goss, 687 n.
_Jordania_, _698_
_Joturus_, _640_
Joues cuirassées, 692
Jugulares, 702 f., 651, 652, 306
Julin, 38, 39, 52
_Julis_, _673_, 674
Jullien, 23
Jumping-Fish, 690

Kalymmocytes, 40, 56, 93, 107
Kelb-el-Bahr, 578
Kidneys, 397 f.;
development, 397;
in different Fishes, 399
Kilch, 311
King-Fish, 628
King of the Herrings, 715
Kner and Steindachner, 626
_Kneria_, _616_;
_K. angolensis_, 616;
_K. spekii_, 616 n.
Kneriidae, _615_, 606
Korotneff, 39
_Kowalevskia_, _68_
Kowalevskiidae, _68_
Kowalevsky, 7 n., 37, 39, 94 n., 113
Krohn, 37
_Krohnius_, _647_
Krukenberg, 271 n.
Kuhl, 36
_Kuhlia_, _657_
Kupffer, 38
Kurtidae, _687_
Kurtiformes, _687_ f., 651, 652
_Kurtus_, _687_;
_K. indicus_, skeleton of, 688
Kyle, 687 n.

_Labeo_, _582_;
_L. falcifer_, 583
_Labidesthes_, _639_
_Labrichthys_, _673_
Labridae _673_, 654, 271, 275;
coloration, 164, 166
_Labrodon_, _674_
_Labrus_, _673_, 674;
pharyngeal teeth, 252, 288;
_L. labrax_, 275;
_L. maculatus_, pharyngeal bones, 673;
_L. rupestris_, 674
Labyrinthiform organs, 292, 293
Lacaze-Duthiers, 38
Lactariidae, _663_, 654
_Lactarius delicatulus_, _663_
_Lactophrys_, _724_
_Laemargus_, _455_;
_L. borealis_, 455, 456;
intestinal caeca, 274;
eggs, 435
_Laïs_, _588_
Lamarck, 36
_Lamna_, _451_;
_L. cornubica_, 451
Lamnidae, _450_
_Lampetra_, _426_;
_L. wilderi_, 427
Lampreys, 425 f.
Lamprididae, _628_, 627
_Lampris_, _628_, 629;
_L. luna_, 628;
coloration, 164
_Lamprogrammus_, _712_
_Lamprologus_, _671_
_Lanarkia_, _524_, 525;
_L. spinosa_, 524
Lancelet, 112
Lang, 31 n.
Langerhans, 112
Lankester, 5 n., 23, 112, 113
_Larimus_, _663_
Larvacea, _64_ f., 64, 110;
structure, 65;
habits, 65;
tail, 66;
classification, 68;
occurrence, 69
Larval Fishes—Teleosts, 417 f., 418, 419;
Cyclostomata, 428;
Crossopterygii, 290, 483, 484;
Chondrostei, 494;
Holostei, 501, 504;
Dipnoi, 514, 515, 517, 518
Larval gills, 290 f.;
Elasmobranchii, 289, 290;
_Polypterus_, 290, 483, 484;
_Heterotis_, 290;
_Gymnarchus_, 290, 418, 419;
_Misgurnus_, 290;
Salmon, 290;
_Protopterus_, 291, 515, 515;
_Lepidosiren_, 291, 517, 518
Larval organs, 418;
adhesive or cement organs, 418, 494, 501, 504, 514, 515, 517, 518;
external gills, 289, 290, 419;
cutaneous gills, 290, 483, 484, 517, 518;
defensive spines, 418
_Lasanius_, _532_;
_L. problematicus_, 532
_Lateolabrax_, _659_
Lateral line sensory organs, 163, 384, 385, 386, 387
_Lates_, _660_
_Latilus_, _661_
Latrididae, _663_, 654
_Latris_, _663_;
_L. hecateia_, nocturnal colour-changes, 170
Launce, 639
Lavaret, 568
Leather Carp, 584
_Lebiasina_, _575_, 578
Lefevre, 83
_Lefua_, _582_
Lemon Sole, 687
_Lentipes_, _689_
_Lepadogaster_, _709_, 191
_Lepidocephalichthys_, _582_
_Lepidocottus_, _698_
_Lepidomeda_, _582_
_Lepidopus caudatus_, _679_
_Lepidorhombus_, _687_;
_L. megastoma_, 687
_Lepidosiren_, _511_, 149, 153, 261, 401;
pectoral fins, 157;
skull, 231, 233;
gills, 286;
larval gills, 291, 517, 518;
lung, 291, 301;
vascular system, 527;
thyroid, 344;
growling sounds, 363;
relations with other Dipnoi, 518, 519;
_L. paradoxa_, 516;
distribution, habits, and food, 516;
nocturnal colour change, 517;
hibernation, 517; {745}
nest, 517;
filaments on pelvic limb of male, 517;
larva, 517, 518
Lepidosirenidae, _511_
Lepidosteidae, _502_
Lepidosteoidei, _495_ f.
_Lepidosteus_, _503_, 149, 153, 160, 258, 262, 273, 274, 283, 284, 291;
scales, 185, 186, 188;
vertebral column, 201, 202, 204;
skull, 229;
alimentary canal, 257;
spiral valve, 268;
pyloric caeca, 274;
air-bladder, 297, 299, 310;
spiracular pseudobranch, 334, 335;
branchial circulation, 334 n., 336;
brain, 376;
gonads, 400, 402, 405, 407;
segmentation of the egg, 409;
distribution, 503;
habits, 503;
breeding, 503;
larvae, 504;
fossil, 504;
_L. osseus_, 503, 504;
_L. platyrhynchus_, pectoral fin, 243;
_L. platystomus_, 503;
_L. viridis_, 503
_Lepidothynnus_, _678_
Lepidotrichia, 234
_Lepidotrigla_, _701_
_Lepidotus_, _498_;
_L. minor_, 497
_Lepomis_, _657_
_Lepophidium_, _713_
_Leporinus_, _576_
_Leptagoniates_, _575_
_Leptecodon_, _623_
_Leptichthys_, _563_
_Leptobarbus_, _582_
Leptocephalid, of _Albula_, 548
_Leptocephalus_, 600, 21 n.;
_L. brevirostris_, 602
_Leptochilichthys_, _570_
_Leptoclinum_, _87_;
section, 86;
spicules, 87;
_L. neglectum_, 80
_Leptoderma_, _570_
_Leptodoras_, _588_
Leptolepididae, _546_, 544
_Leptolepis_, _546_;
_L. dubius_, 546
_Leptopterygius_, _709_
Leptoscopidae, _705_, 703
_Leptoscopus_, _705_
_Leptosomus_, _611_
_Leptotrachelus_, _623_
_Lethrinus_, _665_
_Leucaspius_, _582_
_Leuciscus_, _582_, 288
Leuckart, 37
_Leucosomus_, _582_
Levinsen, 23
Leydig, 584 n.
_Lichia_, _677_
Ling, 649
_Linophryne_, _719_
_Liocassis_, _588_
_Liocetus_, _719_
_Lionurus_, _647_
_Liopropoma_, _659_
_Liparis_, _698_, 699, 411
_Liparops_, _698_
Lipogenyidae, _624_, 622, 623
_Lipogenys_, _624_;
_L. gillii_, 624
_Liposarcus_, _595_
_Lirus_, _643_;
_L. medusophagus_, 643;
_L. perciformis_, 643
_Liuranus_, _601_
Liver, 271;
of Amphioxus, 121, 123
Loaches, 585, 261, 290, 292;
Pond Loach, 585.
_Lobotes_, _658_
Lobotidae, _658_, 653
Locomotion of Fishes, 349 f., 351
Lohmann, 66
Longchamps, de Selys, 29
Lophiidae, _718_
_Lophiomus_, _718_
_Lophius_, _718_, 153;
_L. piscatorius_, 718, 355;
lure, 161, 173;
teeth, 250
Lophobranchii, _628_, 543, 629
_Lopholatilus_, _661_;
_L. chamaeleonticeps_, 661
_Lophotes_, _716_
Lophotidae, _716_
Lorenzini's ampullae, 384
_Loricaria_, _595_, 292
Loricariidae, _594_, 575, 256, 292
Loricariinae, _595_
_Lota_, _648_;
_L. vulgaris_, 649
_Lotella_, _648_
Löwig and Kölliker, 37
_Lucifuga_, _712_, 713, 395;
_L. subterranea_, 361
_Luciobrama_, _582_
_Luciocephalus_, _669_
_Luciogobius_, _689_
_Lucioperca_, _659_
_Luciosoma_, _582_
Lump-Sucker, 699, 162, 321, 408, 415
_Lumpenus_, _709_
Lunel, 635, 682 n.
Lutjaninae, _660_
_Lutjanus_, _660_
Lütken, 614 n., 682 n., 714 n.
_Lutodeira_, 256
Luvaridae, _681_, 676
_Luvarus imperialis_, _681_
_Lycocara_, _712_
_Lycodes_, _712_, 702
_Lycodontis_, _605_
_Lyconus_, _647_
_Lycoptera_, _546_
Lymph-hearts, 342
Lymphatic system, 342
Lymphoid tissue, 348
Lyomeri, 622
_Lyosphaera_, _726_