Chapter XXVIII: Appendix: To the Fishes: Palaeospondylidae—ostracodermi—heterostraci (9)

[58] Huxley, in 1877 (_Man. Anat. Invert. Animals_, p. 674), proposed to
unite the Enteropneusta with the Tunicata as Pharyngopneusta, in
allusion to the gill-slits connected with the pharynx; but the view
was first defended in detail by Bateson.

[59] See, for example, Minot, _Amer. Nat_. xxxi. 1897, p. 927.

[60] See MacBride, _Quart. J. Micr. Sci_. xl. 1898, p. 589; xliii. 1900,
p. 351.

[61] Bury, _Quart. J. Micr. Sci_. xxix. 1889, p. 409; xxxviii. 1896, p.
125; MacBride, _ibid_. xxxviii. p. 395; Masterman, _Tr. R. Soc.
Edinb_. xl. Pt. ii. No. 19, 1902, p. 403.

[62] This view was definitely formulated by Metschnikoff in 1881 (_Zool.
Anz_. iv. 1881, pp. 139, 153).

[63] Cf. Morgan, _J. Morphol_. v. 1891, p. 445; ix. 1894, pp. 64-66.

[64] Cf. Lang, _Jena. Zeitschr_. xxv. 1891, p. 1.

[65] _J. Morphol_. ix. p. 72.

[66] _Mém. Mus. Paris_, ii. 1815.

[67] _Mém. s. l. Anim. s. Vert_. Pt. ii. Paris, 1816.

[68] _Zoologia Danica_, iv. 1806.

[69] _Hist. Nat. d. Anim. sans Vert_. Paris, 1815-1822, t. iii.

[70] _Mém. Instit. Paris_, xviii. 1842.

[71] _Zur vergl. Physiol. Wirbellos. Thiere_, Brunswick.

[72] _Comptes Rendus_, Paris, xxii; and _Ann. Sci. Nat_. ser. 3 (Zool.) v.

[73] _Phil. Trans_. 1851; _Trans. Linn. Soc_. xxiii. 1860.

[74] _Mém. Acad. St. Pétersbourg_ (7), x. 1866.

[75] _Mém. Instit. Paris_, xviii. 1842.

[76] _Arch. mikr. Anat_. vi. 1872.

[77] _Mém. Soc. Phys. Hist. Nat. Genève_, xxi. 1872.

[78] _Arch. Zool. Expér_. i. 1872.

[79] _Synascidien der Bucht von Rovigno_, Wien, 1883.

[80] _Challenger Reports_, Tunicata, Part i. vol. vi. 1882; Part ii. vol.
xiv. 1886; Part iii. vol. xxvii. 1888.

[81] _Ann. Mag. Nat. Hist_. (3) xi. 1863, p. 153; _Journ. Linn. Soc_.
1868, etc.

[82] _Denkschr. Akad. Wiss. Wien_, 1875 and 1877.

[83] _Arch. Zool. Expér_. iii. 1874, and vi. 1877; _Mém. Instit. Paris_,
xlv. 1892.

[84] _Vid. Medd. Nat. For_. Copenhagen, 1880, 1882, 1884, etc.

[85] _Nat. Tijdschr. Ned.-Indie_, 1885, etc.

[86] _Journ. Linn. Soc. Zool_. xv. xxiii. and xxiv.; _Cat. of Tunicata in
Australian Museum_, 1899; also _Challenger Reports_ (see _note_ 80).

[87] _Arch. de Biol_. ii.

[88] "The Genus _Salpa_," _Mem. J. Hopkins Univ_. 1893.

[89] _Zeits. wiss. Zool_. 1876, 1878; _Mitth. Zool. Stat. Neapel_, 1883,
etc.

[90] _Jen. Zeitschr_. 1886, 1888, etc.; also Bronn's _Thier-Reich_.

[91] _Mitth. Zool. Stat. Neapel_, 1893 and 1897; and _Zeits. wiss. Zool_.
1895 and 1896.

[92] _Journ. Anat. Phys_. Paris, xxi. 1885.

[93] _Fauna and Flora G. v. Neapel_, Monogr. x. 1884.

[94] These sphincters close the only openings through the tough test so
effectually that when collectors are preserving Ascidians in alcohol
it is advisable to make one or more slits in the test to allow the
sea-water to escape and the spirit to enter.

[95] Except in Cynthiidae and Botryllidae where it is dorsal.

[96] The early stages of _Ciona_, of which Castle has given a very
complete account (_Bull. Mus. Comp. Zool_. xxvii. No. 7, 1896),
differ in some points from those of _Ascidia_ described here.

[97] Possibly the diverticulum may be wholly derived from the neural tube
(see Willey, _Quart. J. Micr. Sci_. 1893).

[98] See Lohmann, _Schrift. Naturw. Ver. Schlesw.-Holst_. xi. 1899, 347.

[99] _Arch. de Biologie_, vi. 1887.

[100] See _Journ. of Morphology_, xii.-xiv. 1896-1898.

[101] _Bull. Mus. Comp. Zool_. xxxv. No. 4, 1899, p. 59.

[102] _Journ. Morph_. xii. 1896, p. 149.

[103] See Pizon, _Ann. des Sci. Nat_. 7^e sér. Zool. xiv. 1892.

[104] "Oozooid" and "blastozooid" have not always been used in the same
sense. It is best to regard as oozooid the first member of a new
colony derived from an embryo formed by the fertilisation of an ovum,
and to call the remaining ascidiozooids produced by gemmation the
blastozooids.

[105] According to Kowalevsky. Salensky, however, considers that the atrial
aperture closes, and that a new surface depression appears later.

[106] See Barrois, _Journ. d'Anat. et Physiol_. 1885.

[107] _Mitth. Z. Stat. Neapel_, x. 1891.

[108] The most useful works on the Salpidae are Traustedt, _Vid. Selsk.
Skr_. ii. 8, 1885, Copenhagen; and Brooks's "The genus Salpa," _Johns
Hopkins Biolog. Memoirs_, ii. 1893.

[109] According to Metcalf, _Salpa cylindrica_ is protandrous.

[110] For a more detailed account of these subdivisions of the Salpidae,
and other groups, see Herdman's "Revised Classification of Tunicata,"
_Journ. Linn. Soc_., Zool., xxiii. 1891, p. 558.

[111] See Herdman, _Challenger Report_ on Tunicata, part iii. 1888, p. 88;
and Metcalf, _Johns Hopkins Univ. Circ_. No. 106, 1893, and _Zool.
Jahrb. Abth. Anat_. xiii. 1900, p. 572.

[112] Although the correct systematic name of the commonest species is
_Branchiostoma lanceolatum_ (Pallas), it is convenient in
non-systematic usage to employ the term "Amphioxus," which is in
general use in zoological laboratories.

[113] _Quart. Journ. Micr. Sci_. xlv. March 1902, p. 493.

[114] The cerebral eye and the pigment spots of the spinal cord are
especially prominent in the oceanic species _Branchiostoma
pelagicum_, Günther.

[115] The mesoblastic somites in Figs. 84 and 85 are all derivatives of the
larger posterior pair of coelomic pouches, the smaller more anterior
ones not being shown. For further details in regard to the coelomic
pouches see MacBride, _Quart. Journ. Micr. Sci_. xliii. p. 351, 1900.

[116] I have to thank Mr. Walter Tattersall, B.Sc., working in my
laboratory, for a detailed summary and discussion of the various
published schemes from which this table has been drawn up. He has
also filled up for me the map (Fig. 90) showing the geographical
distribution of the species. (See also _Trans. Biol. Soc. Liverpool_,
vol. xvii. 1903, p. 269.)

[117] A coelom formed by the union of one or more pairs of primitively
distinct coelomic cavities.

[118] Cf. p. 129.

[119] Cf. p. 391.

[120] Gadow, _A Classification of Vertebrata_, 1898, p. 4.

[121] Sucker-like modifications of the ventral surface of the body, in
which the paired fins take no part, are present on the throat in many
Fishes which frequent hill-streams, as in some small African and
Asiatic Cyprinidae (e.g. _Discognathus_) and a few Siluridae (e.g.
_Euglyptosternum_).

[122] Saville Kent, _The Naturalist in Australia_, London, 1897, p. 150.

[123] _Ibid_. p. 167

[124] _Ibid_. p. 168.

[125] _Ibid_. p. 173.

[126] _Ibid_. p. 188.

[127] Cunningham and MacMunn, _Phil. Trans_. 184, 1893, p. 765, where
references to many other papers are given.

[128] _Ablette_ is the French name for the Bleak.

[129] Either singly or in combination with lime (Guaninkalk), guanin is
often present in the tissues of Fishes (air-bladder, gall-bladder,
subcutaneous connective tissue, muscle-fasciae, peritoneum, and the
retinal epithelium and tapetum of the eye). For references see
Cunningham and MacMunn, _op. cit_. p. 781 _et seq_.

[130] Cunningham and MacMunn, _op. cit_. pp. 768 and 771.

[131] A. Agassiz, _Bull. Mus. Comp. Zool_., Camb. U.S.A., xxiii. 1892, p.
189.

[132] Cunningham and MacMunn, _op. cit_. p. 791, _et seq_.

[133] _Ibid_. p. 800.

[134] Saville Kent, _Nat. Austr_. p. 163.

[135] Poulton, _The Colours of Animals_, Internat. Scientific Series,
London, 1890, p. 82.

[136] Percy St. John, quoted by Day, _Fishes of Great Britain and Ireland_,
London, 1880-84, ii. p. 58.

[137] Poulton, _op. cit_. p. 82.

[138] _Ibid_. p. 86.

[139] Cunningham and MacMunn, _op. cit_. p. 773.

[140] C. Stewart, quoted by Poulton, _op. cit_. p. 67.

[141] Saville Kent, _op. cit_. p. 186, describes the colours of the living
Fish as "various shades of light crimson and lilac."

[142] Günther, _Study of Fishes_, London, 1880, p. 524.

[143] Poulton, _op. cit_. p. 72.

[144] For another view of the use of the "lure," see Cunningham,
_Marketable British Marine Fishes_, London, 1896, p. 338.

[145] Günther, _Chall. Reports, Zool_. vol. xxii. 1887, p. 50.

[146] Suggested by Lütken; Günther, _l. c_.

[147] Garstang, quoted by Poulton, _op. cit_. p. 165.

[148] See p. 364.

[149] E. Ray Lankester, _Proc. Roy. Soc_. 1873, p. 70.

[150] Cunningham and MacMunn, _op. cit_. p. 781.

[151] W. Newton Parker, _P.Z.S._ 1888, p. 359.

[152] Günther, _Trans. Zool. Soc_. vi. 1869, p. 437.

[153] Ibid., _Study of Fishes_, Edinburgh, 1880, p. 191.

[154] _Ibid_. p. 192.

[155] _Ibid_. p. 190.

[156] Lendenfeld, _Chall. Reports, Zool_. xxii. 1887, p. 277. For
references to papers by Leydig, Ussow, Emery, and others, see
Lendenfeld, _op. cit_.

[157] Moseley, _Challenger Reports, Zool_. xxii. 1887, p. 267.

[158] C. W. Wilson, _Journ. Morph_. xv. 1899, p. 667.

[159] Burckhardt, _Ann. Mag. Nat. Hist_. (7), vi. 1900, p. 568.

[160] Ibid. _op. cit_. p. 558.

[161] Wiliamson, _Phil. Trans_. cxxxix. 1849, p. 435; Hertwig, _Morph.
Jahrb_. ii. 1876, p. 328; v. 1879, p. 1; vii. 1882, p. 1; Klaatsch,
_ib_. xvi. 1890, p. 97 _et seq_., p. 209 _et seq_.

[162] Klaatsch has since affirmed the epidermic origin of the scleroblasts,
_ibid_. xxi. 1894, p. 153.

[163] Klaatsch, _Morph. Jahrb_. xvi. 1890, p. 125; Nickerson, _Bull. Mus.
Comp. Zool. Harvard_, xxiv. 1893, p. 115.

[164] Ryder, _Proc. Acad. Nat. Sci. Philadelphia_, 1892, p. 219; Smith
Woodward, _Nat. Sci_. iii. 1893, p. 448.

[165] Smith Woodward, _op. cit_. p. 449.

[166] O. Hertwig, _Morph. Jahrb_. ii. 1876, p. 374; Klaatsch, xvi. 1890, p.
146.

[167] Klaatsch, _op. cit_. p. 178.

[168] O. Hertwig, _Morph. Jahrb_. vii. p. 15.

[169] O. Hertwig, _Morph. Jahrb_. vii. p. 7.

[170] _Ibid_. vii. p. 29.

[171] _Ibid_. ii. p. 334.

[172] Hoffbauer, "Die Altersbestimmung des Karpfen an seiner Schuppe."
_Jahresb. des Schlesischen Fischerei-Vereins_, 1899; J. Stewart
Thomson, _Journ. Marine Biol. Assoc_. vi. No. 3, 1902, p. 373.

[173] Günther, _Phil. Trans_. clxi. 1871, p. 516; Klaatsch, _op. cit_. p.
209.

[174] This portion of the chapter is mainly based on the important
researches of Dr. Gadow and Miss Abbott. See _Phil. Trans_. 186,
1895, p. 163 _et seq_. where copious references to the work of other
writers are given.

[175] Neuromeres are body-segments defined and limited by the exits of the
successive pairs of spinal nerves from the neural canal.

[176] Gadow, _op. cit_. p. 190.

[177] Schneider, _Beitr. z. vergl. Anat. u. Entwickl. Wirbelth_., Berlin,
1879, p. 51; also Gadow, _op. cit_. p. 196.

[178] Smith Woodward, _Brit. Mus. Cat. Fossil Fishes_, Pt. i. 1889, p.
xvii.

[179] Hasse, _Das natürliche Syst. d. Elasmobranchier_; etc., Jena, 1879,
p. 30, _et seq_.

[180] Gadow, _op. cit_. p. 194; Ridewood, _Journ. Linn. Soc. Zool_. xxvii.
1899, p. 46.

[181] Günther, _Phil. Trans_. 161, 1872, p. 526; Wiedersheim, _Morph.
Studien_, Jena, 1880, Pt. i. p. 65; Gadow, _op. cit_. p. 198.

[182] Bridge, _P.Z.S._ 1897, p. 722.

[183] Gadow, _op. cit_. p. 201, _et seq_.

[184] See Budgett, _Trans. Zool. Soc_. xvi. Pt. vii. 1902, p. 315.

[185] Zittel, _Handb. d. Palaeontologie_, iii. 1887-1890, p. 137 _et seq_.;
Gadow, _op. cit_. p. 208.

[186] F. M. Balfour and W. N. Parker, _Phil. Trans_. 173, 1882, p. 388.

[187] As additional primary cranial elements mention may be made of a pair
of independently developed "alisphenoid" cartilages, which lie in
front of the parachordals between the brain and the eyes, and above
the trabeculae, and form a considerable part of the inter-orbital
region of the cranium. See Sewertzoff, _Anat. Anz_. xiii. 1897, p.
413; ibid., _Kupffer Festschrift_, Jena, 1899, p. 281.

[188] W. K. Parker, _Trans. Zool. Soc_. x. 1878, p. 189.

[189] Huxley, _P.Z.S._ 1876, p. 40.

[190] W. K. Parker, _Phil. Trans_. 163, 1873, p. 95.

[191] M‘Murrich, _Proc. Canadian Inst_. (N.S.) ii. Toronto, 1884, p. 278;
Cole, _Trans. Linn. Soc_. vii. Pt. v. 1898, p. 131.

[192] W. K. Parker, _Phil. Trans_. 174, Pt. ii. 1883, p. 411; Huxley,
_Journ. Anat. and Phys_. x. 1876, p. 412; Howes, _Trans. Biol. Soc.
Liverpool_, vi. 1891, p. 122.

[193] Huxley, _op. cit_. p. 421.

[194] W. K. Parker, _Phil. Trans_. 174, 1883, pp. 376-405; Ayers and
Jackson, _Journ. Morph_. xvii. 1901, p. 193.

[195] Huxley, _P.Z.S._ 1876, p. 40, _et seq_.

[196] Dollo, _Bull. Soc. Belge Géol_. etc. ix. 1895, p. 110.

[197] Hubrecht, _Niederländ. Archiv f. Zool_. iii. 1877, p. 255.

[198] W. K. Parker, _Phil. Trans_. 173, 1882, p. 139; Bridge, _Phil.
Trans_. 169, 1878, p. 683.

[199] Traquair, _Journ. Anat. and Phys_. v. 1871, p. 166; Bridge, _Proc.
Birm. Phil. Soc_. vi. 1888, p. 118; Budgett, _Trans. Zool. Soc_. xvi.
Pt. vii. 1902, p. 315.

[200] Budgett, _Trans. Zool. Soc_. xv. 1900, p. 334.

[201] Sagemehl, _Morph. Jahrb_. ix. 1884, p. 177.

[202] W. K. Parker, _Phil. Trans_. 173, 1882, p. 443.

[203] Bridge, _P.Z.S._ 1895, p. 302.

[204] Sagemehl, _Morph. Jahrb_. x. 1885, p. 1; xxvii. 1891, p. 489.
Swinnerton, _Quart. J. Micr. Sci_. xlv. 1902, p. 503.

[205] Günther, _Phil. Trans_. 161, 1871, p. 521; Huxley, _P.Z.S._ 1876, p.
31; Wiedersheim, _Morph. Stud_. i. Jena, 1880, p. 46; Bridge, _Trans.
Zool. Soc_. xiv. 1898, p. 350.

[206] Ridewood, _P.Z.S._ 1894, p. 632.

[207] _Ibid_. p. 638.

[208] Traquair, _Ann. Mag. Nat. Hist_. (5), ii. 1878, p. 1.

[209] Thacker, _Trans. Connecticut Acad_. iii. 1877, p. 281; Mivart,
_Trans. Zool. Soc_. x. 1879, p. 439; Bridge, _Linn. Soc. Journ.
Zool_. xxv. 1896, p. 530.

[210] Goodrich, _Quart. Journ. Micr. Sci_. 47, 1903-1904, p. 465.

[211] Smith Woodward, _Nat. Sc_. i. 1892, p. 29.

[212] Smith Woodward, _Brit. Mus. Cat. Foss. Fishes_, ii. 1891, p. 335.

[213] W. K. Parker, _Shoulder-girdle and Sternum of Vertebrata_, Ray Soc.
1868; Gegenbaur, _Untersuch. Vergl. Anat. Wirbelth_. Pt. ii. Leipzig,
1865; Wiedersheim, _Das Gliedmassenskelet d. Wirbelth_. Jena, 1892.

[214] Traquair, _Nature_, 62, 1900, p. 502.

[215] Traquair, _Trans. Roy. Soc. Edin_. xxxix. 1899, p. 843.

[216] It is more probable that in most existing Teleostomi the pelvic
girdle has undergone complete suppression, in which case these
cartilages are vestiges and not rudiments.

[217] See, however, Goodrich, _Quart. Journ. Micr. Sci_. xlv. 1901, p. 311.

[218] Bashford Dean, _Anat. Anz_. xi. 1896, p. 673.

[219] Budgett, _Trans. Zool. Soc_. xvi. Part vii. 1902, p. 328.

[220] Thacker, _Trans. Connecticut Acad_. iv. 1877, p. 233.

[221] Traquair, _Geol. Mag_. vii. 1890, p. 15; Goodrich, _l.c._

[222] Haswell, _Proc. Linn. Soc. N.S.W._ ix. 1884, p. 71; Howes, _P.Z.S._
1887, p. 3.

[223] Warren, _Quart. Journ. Micr. Sci_. xlv. 1902, p. 631.

[224] See Ridewood, _Nat. Sci_. viii. 1896, p. 391, for references.

[225] Ridewood, _op. cit_. p. 390.

[226] For references see Howes, _Linn. Soc. Journ. Zool_. xxiii. 1890, p.
381.

[227] Howes, _op. cit_.

[228] Macallum. Reprinted from _Proc. Canadian Instit. N.S._ ii. 1884, p.
387.

[229] Howes, _op. cit_.

[230] Howes, _P.Z.S._ 1890, p. 669.

[231] Balfour and Newton Parker, _Phil. Trans_. 173, 1882, p. 425.

[232] Newton Parker, _Trans. Roy. Irish Acad_. xxx. 1892, p. 140.

[233] Günther, _Phil. Trans_. 161, 1871, pp. 542-543.

[234] Owen, _Anat. Phys. Vertebrates_, London, 1866, i. p. 424.

[235] For the histology of the alimentary canal and its glands in Fishes,
see Leydig, _Lehrb. d. Histol. d. Menschen u. d. Tiere_, 1857; Id.
_Beitr. zu mikrosk. Anat. u. Entwickl. d. Rochen u. Haie_, Leipzig,
1852; Id. _Anat.-histol. Untersuch. üb. Fische u. Reptilien_, Berlin,
1853; Molin, _Sitz. d. k. Akad. d. Wiss. zu Wien_, v. 1850, p. 416;
Macallum, _Proc. Canadian Inst_. N.S. ii. 1884, p. 387; Id. _Journ.
Anat. and Phys_. xx. 1886, p. 604; N. Parker, _Trans. Roy. Irish
Acad_. xxx. 1893, p. 109; Ayers, _Jen. Zeitsch_. xviii. 1885, p. 479;
Edinger, _Archiv f. mikr. Anat_. xiii. 1876, p. 651; Trinkler,
_Archiv f. mikr. Anat_. xxiv. 1884, p. 174. Also Oppel, _Lehrb. d.
vergl. mikrosk. Anat. d. Wirbeltiere_, i.-ii. Jena, 1896-97, where
numerous other references are given.

[236] Owen, _op. cit_. p. 418.

[237] Owen, _l.c._

[238] Hyrtl, _Lepidosiren paradoxa. Abhand. d. böhm. Gesell. d. Wiss_.
1845, p. 629.

[239] Newton Parker, _op. cit_.

[240] Paul Mayer, _Mitt. zool. Stat. zu Neapel_, viii. 1888, p. 307.

[241] Wiedersheim, _Lehrb. d. vergl. Anat. d. Wirbelthiere_, ed. ii. Jena,
1886, p. 576.

[242] Owen, _op. cit_. p. 415.

[243] T. Jeffery Parker, _Trans. Zool. Soc_. xi. 1879, p. 49.

[244] Jeffery Parker, _op. cit_. pl. xi. Fig. 5.

[245] _Ibid_. p. 58.

[246] _Ibid_. p. 58.

[247] _Ibid_. p. 59.

[248] _Ibid_. p. 58, pl. xi. Fig. 6.

[249] Günther, _op. cit_. p. 544.

[250] Newton Parker, _op. cit_. p. 141.

[251] Macallum, _Journ. Anat. and Phys_. xx. 1886, pp. 618, 619.

[252] Owen, _op. cit_. p. 424.

[253] Macallum, _l.c._

[254] Balfour and Newton Parker, _op. cit_. p. 425.

[255] Cuvier and Valenciennes, _Hist. Nat. d. Poiss_. xix. 1846, p. 151.

[256] Rathke, _Üb. d. Darmkanal u. d. Zeugungsorgane d. Fische_, Halle,
1824, pp. 62 f.

[257] Edinger, _op. cit_. p. 678.

[258] T. Jeffery Parker, _op. cit_. p. 55.

[259] _Archiv f. mikr. Anat_. xiii. 1876.

[260] Krukenberg, quoted by Miss Alcock, _Journ. Anat. and Phys_. xiii.
(N.S.), 1899, p. 613.

[261] Stannius, _Handb. d. Zool_., Berlin, 1854, ii. p. 201; Owen, _op.
cit_. p. 425.

[262] Macallum, reprinted from _Proc. Canadian Institute_, N.S. ii. 1884,
p. 407.

[263] Newton Parker, _op. cit_. p. 138.

[264] Macallum, _Journ. Anat. and Phys_. xx. 1886, p. 632.

[265] Legouis, _Ann. Sci. Nat_. (5), xvii. 1873, Art. 8; and xviii. 1873,
Art. 3. Also Macallum, _op. cit_. p. 629.

[266] Newton Parker, _op. cit_. pp. 138-139.

[267] Turner, _Journ. Anat. and Phys_. vii. 1873, p. 233.

[268] Stannius, _op. cit_. pp. 197, 198; Owen, _op. cit_. p. 428, _et seq_.

[269] For references, see Macallum, _Journ. Anat. and Phys_. xx. p. 624 _et
seq_.

[270] Wiedersheim, _op. cit_. p. 556.

[271] Howes, _op. cit_. p. 393.

[272] Günther, _Challenger Reports_, "Zool." xxii. 1887, p. 3; Garman,
_Bull. Mus. Comp. Zool. Camb. Mass_. xii. 1885, p. 20.

[273] Günther, _op. cit_. p. 545; Newton Parker, _op. cit_. p. 137.

[274] Howes, _op. cit_. p. 393 _et seq_.

[275] Graham Kerr, _P.Z.S._, 1901, ii. p. 484.

[276] In those Elasmobranchs which have more than five branchial clefts
there is a corresponding increase in the number of branchial arches
and hemibranchs.

[277] Ridewood, _Anat. Anz_. xi. 1895, p. 425.

[278] Garman, _Bull. Mus. Comp. Zool. Harvard_, xii. 1885, p. 1; Günther,
_Challenger Reports_, "Zool." xxii. 1887, p. 2.

[279] In the _Ammocoetes_ stage the gill-sacs open directly into the larval
pharynx, which is retained as the branchial canal, the oesophagus of
the adult being an independent and later formation.

[280] Dohrn, _Mitth. Zool. Stat. Neapel_, vi. 1886, p. 49.

[281] Shipley, _Quart. J. Micr. Sci_. xxvii. 1887, p. 350.

[282] _Cf_. p. 343.

[283] See p. 423.

[284] Howes (_P.Z.S._ 1893, p. 730) has described certain remarkable
variations in the respiratory organs of _Petromyzon_ and _Myxine_.

[285] In certain Teleosts more or fewer of the branchial arches may lose
their gills. This reduction attains its maximum in the singular
Indian amphibious Fish, _Amphipnous cuchia_, where only the second
arch has a biserial gill, the remaining arches being wholly devoid of
gills (_cf_. p. 598).

[286] Balfour, _Comp. Embryol_. ii. 1881, p. 62.

[287] Ramsay Wright, _Journ. Anat. and Phys_. xix. 1885, p. 476.

[288] Sagemehl, _Morph. Jahrb_. ix. 1884, p. 213.

[289] Ramsay Wright, _op. cit_. p. 482.

[290] See p. 335.

[291] F. W. Müller, _Arch. Mikrosk. Anat_. xlix. 1897, p. 463.

[292] Ramsay Wright, _op. cit_. p. 492.

[293] F. Maurer, _Morph. Jahrb_. ix. 1884, p. 229; xiv. 1888, p. 175.

[294] Günther, _Phil. Trans_. clxi. 1871, p. 511; Baldwin Spencer, _Macleay
Memorial Volume_, 1892, p. 1.

[295] Newton Parker, _Trans. Roy. Irish Acad_. xxx. 1892, p. 161; Bridge,
_Trans. Zool. Soc_. xiv. 1898, p. 361.

[296] Boas, _Morph. Jahrb_. vi. 1880, p. 345. See Fig. 201, p. 340.

[297] Bischoff, _Lepidosiren paradoxa_, Leipzig, 1840; Hyrtl, _Abhand. d.
böhm. Gesellsch_. 1845, p. 637; also Bridge, _op. cit_. pp. 344, 345.

[298] Turner, _Journ. Anat. and Phys_. xiv. 1879, p. 273. For references to
other writers see Turner, _op. cit_.

[299] For this information, which was based on an examination of a
specimen, parts of which are now in the Cambridge University Museum,
I am indebted to Dr. Harmer.

[300] Van Beneden, quoted by Turner, _op. cit_. p. 282.

[301] Andrew Smith, also quoted by Turner, _op. cit_. p. 281.

[302] Dahlgren, _Zool. Bull_. ii. 3, Boston, 1898; Allis, _Anat. Anz_.
xviii. 1900, p. 257.

[303] M‘Kendrick, _Journ. Anat. and Phys_. xiv. 1879, p. 461.

[304] _Naturalist in Celebes_, London, 1889, p. 30.

[305] _Nature_, xxxix. 1889, p. 285.

[306] Budgett, _Trans. Zool. Soc_. xvi. Pt. ii. 1901, p. 126.

[307] Götte, quoted by Balfour, _Comp. Embryol_. ii. 1881, p. 62.

[308] Steindachner, _Sitz. d. k. Akad. d. Wiss_. i. 1869, p. 103; Hyrtl,
_ibid_. p. 109; Budgett, _op. cit_. p. 118.

[309] Boulenger, _P.Z.S._ 1899, p. 554.

[310] Semon, _Zoologische Forschungsreisen in Australien_, Pt. i. p. 44,
and Atlas.

[311] Burt G. Wilder, _Proc. Amer. Ass. Adv. Sci_. 1875, p. 151; _ibid_.
1877, p. 306.

[312] _Ann. d. Sci. Nat_. sér. 6, vii. 1878, Art. 5.

[313] Baldwin Spencer, _op. cit_. p. 3.

[314] Sörensen, _Journ. Anat. and Phys_. 1894, p. 127-138.

[315] Moreau, _Ann. d. Sci. Nat_. sér. 6, _Zool_. iv. 1876, Art. 8, p. 62.

[316] Erman, _Gilbert Ann. d. Physik_. xxx. 1808, p. 113.

[317] Jobert, _op. cit_.; _ibid_. v. 1877, Art. 8.

[318] Zograff, _Quart. J. Micr. Sci_. xxviii. 1888, p. 501.

[319] Hyrtl, _Sitz. d. k. Akad. Wiss_. x. 1853, p. 148.

[320] Hyrtl, _Denksch. k. Akad. Wiss. Wien_. xxiii. 1863, p. i.; _ibid_. x.
1855, p. 48.

[321] Hyrtl, _ibid_. viii. 1854, p. 185.

[322] Hyrtl, _ibid_. xxi. 1863, p. 7; Sagemehl, _Morph. Jahrb_. xii. 1887,
p. 307.

[323] Taylor, _Edin. Journ. Sci_. v. 1831, p. 33; Hyrtl, _Denksch. k. Akad.
Wiss. Wien_. xiv. 1858, p. 39.

[324] Hyrtl, _SB. Akad. Wiss. Wien_. xi. 1853, p. 302; Day, _Linn. Soc.
Journ. Zool_. xiii. p. 198.

[325] Burne, _Journ. Linn. Soc. Zool_. xxv. 1894, p. 48.

[326] For much interesting information on aerial respiration in Fishes, see
Day, _op. cit_.; also _P.Z.S._ 1868, p. 274; and Dobson, _ibid_.
1874, p. 312.

[327] Semper, _Animal Life_, Intern. Sci. Series, London, 1881, p. 172.

[328] Miklucho-Maclay, _Jen. Zeitsch_. iii. 1867, p. 448.

[329] Wiedersheim, _Lehrb. d. vergl. Anat. d. Wirbelth_. ed. 2, Jena 1886,
p. 616.

[330] The glottis is furnished with a structure analogous to the
epiglottis-like plate of _Protopterus_ (Wiedersheim, _op. cit_. p.
616).

[331] Balfour and Newton Parker, _Phil. Trans_. 173, Part ii. 1883, p. 425.

[332] Günther, _Phil. Trans_. 161, 1871, p. 511; Baldwin Spencer,
_Zoologische Forschungsreisen in Australien_ (Semon), i. Jena 1898,
p. 53.

[333] Newton Parker, _Trans. Roy. Irish Acad_. xxx. 1892, p. 109; Baldwin
Spencer, _op. cit_. p. 54.

[334] Henle, quoted by Howes, _P.Z.S._ 1887, p. 501; also Wiedersheim, _op.
cit_. p. 622 and Fig. 483.

[335] Bischoff, _Ann. d. Set. Nat_. (2) _Zool_. xiv. 1840, p. 136.

[336] Stannius, _Handb. d. Zool_. Berlin ii. 1854, p. 220.

[337] Günther, _Study of Fishes_, Edinburgh, 1880, p. 457.

[338] Bridge and Haddon, _Phil. Trans_. B, 184, 1893, p. 209.

[339] Reinhardt, quoted by Stannius, _op. cit_. p. 225.

[340] Cuvier and Valenciennes, _Hist. Nat. d. Poissons_, xxi. 1848, p. 139;
Bridge, _Journ. Linn. Soc. Zool_. xxvii. 1900, p. 503.

[341] Day, _P.Z.S._ 1871, p. 703.

[342] Sörensen, "Lydorganer hos Fiske," Copenhagen, 1884, p. 85; Kner, _SB.
k. Akad. Wiss. Wien_, xi. 1853, p. 138.

[343] Cuvier and Valenciennes, _op. cit_. v.

[344] Günther, _Brit. Mus. Cat. Fishes_, ii. 1860, p. 313.

[345] Moreau, _Compt. Rend_. lix. 1864, p. 436.

[346] J. Müller, _Ber. d. k. Akad. d. Wiss. Berlin_, 1842, p. 177.

[347] Bridge and Haddon, _op. cit_. p. 234, Pl. II. Fig. 18.

[348] _Ibid_. p. 216.

[349] Weber, _De aure et auditu Hominis et Animalium_, Leipzig, 1820, p.
73.

[350] Moreau, _Compt. Rend_. lxxx. 1875, p. 1247.

[351] Coggi, _Mitth. Zool. Stat. Neapel_, vii. 1887, p. 381; Swale Vincent
and Stanley Barnes, _Journ. Anat. and Phys_. xxx. 1896, p. 545.

[352] For the blood-supply of the air-bladder see Chap. XII.

[353] See Chaps. XIV. XIII. and X.

[354] Moreau, _Ann. d. Sci. Nat_. (6) iv. 1876, Art.

[355] Moreau, _op. cit_.

[356] Bridge and Haddon, _op. cit_. p. 286.

[357] Semper, _Animal Life_, Internat. Sci. Series, London, 1881, p. 321.

[358] Moreau, _op. cit_. pp. 3, 4.

[359] J. Müller, _Vergl. Anat. d. Myxinoiden_, Pt. iii. (1839), Berlin,
1841, p. 186. For an account of the vascular system of _Bdellostoma_
see Jackson, _Journ. Cincinnati Soc. Nat. Hist_. xx. 1901, p. 13.

[360] T. Jeffery Parker, _Phil. Trans_. 177, Pt. ii. 1886, p. 702. For
references to Elasmobranchs in general, see Parker, _op. cit_. p.
725.

[361] In the common Dog-Fish (_Scyllium canicula_) each lateral vein joins
the posterior cardinal near the junction of the latter with the
Cuvierian duct, the subclavian vein from the pectoral fin opening
directly into the corresponding Cuvierian duct.

[362] Jourdain, _Ann. Sci. Nat_. (4), xii. 1859, p. 321; M‘Kenzie, Reprint
from the _Proc. Canadian Institute_ (N.S.) ii. 1884, p. 428. For
references to Hyrtl and other writers, see Jourdain, _op. cit_.

[363] Balfour, _Comparative Embryology_, London, ii. 1881, pp. 66, 91, and
96.

[364] A subintestinal vein is also present in adult Holocephali (e.g.
_Callorhynchus antarcticus_), T. Jeffery Parker, _op. cit_. p. 706.
The persistence of this vein in adult Fishes is associated with the
presence of a well-developed spiral valve.

[365] Budgett, _Trans. Zool. Soc_. xiv. Pt. vii. 1901, p. 332.

[366] Günther, _Phil. Trans_. 161, 1872, p. 535; Baldwin Spencer, _Macleay
Memorial Volume_, 1894, p. 17.

[367] Baldwin Spencer, _op. cit_. pp. 24, 30-31. Not represented in Fig.
191.

[368] Hochstetter, _Morphol. Jahrb_. xiii. 1888, p. 153.

[369] The vertebral vein, which is present only on the right side, may
represent the reduced anterior portion of the right posterior
cardinal, as Baldwin Spencer (_op. cit_.) has suggested.

[370] As an abnormality the adult Frog may retain the embryonic connexion
of the right anterior abdominal vein with the heart (Buller, _Journ.
Anat. and Phys_. iii. 1896, p. 211).

[371] Newton Parker, _Trans. Roy. Irish Acad_. xxx. 1892, p. 179.

[372] Hyrtl, _Abhand. d. Böhm. Gesellsch_. 1845, p. 643.

[373] There is an incomplete auricular septum in the Holocephali (e.g.
_Chimaera monstrosa_), see Ray Lankester, _Trans. Zool. Soc_. x.
1879, p. 502.

[374] Stannius, _Handb. d. Anat. d. Wirbelth_. Berlin, ii. 1854, p. 235;
Boas, _Morphol. Jahrb_. vi. 1880, p. 527.

[375] Boas, _Morphol. Jahrb_. vi. 1880, p. 321.

[376] _Ibid. op. cit_.

[377] J. Müller, _Vergl. Anat. d. Myxinoiden_, Pt. iii. (1839) Berlin 1841
p. 179.

[378] T. Jeffery Parker, _Phil. Trans_. 177, Pt. ii. 1886, p. 686; cf. H.
Ayers, _Bull. Mus. Comp. Zool. Harvard_, xvii. No. 5, 1889, p. 191.

[379] _Chlamydoselachus_ is more primitive in this respect, and has but a
single efferent vessel for the two hemibranchs of each arch, which
corresponds with the more anterior of the two in _Mustelus_ (Ayers,
_op. cit_.).

[380] Cf. footnote to p. 332.

[381] Note, however, that in the young _Lepidosteus_ there are two efferent
vessels in each arch, which, nevertheless, differ from those of
_Mustelus_ in uniting to form an epibranchial artery before joining
the dorsal aorta (F. W. Müller, _Arch. Mikr. Anat_. xlix. 1897, p.
463).

[382] T. Jeffery Parker, _op. cit_. p. 691.

[383] Cf. Figs. 195 and 196.

[384] Ramsay Wright, _Journ. Anat. and Phys_. xix. 1885, p. 482; F. W.
Müller, _op. cit_.

[385] These vessels are not to be regarded as homologous with the primitive
paired aortae of Amphioxus and the embryos of higher Vertebrates. The
true dorsal aorta sometimes persists as a median vestigial vessel
which traverses the circulus cephalicus.

[386] For the relations of the efferent branchial vessels to the cephalic
circle and the median dorsal aorta in different Teleosts, see
Ridewood, _P.Z.S._ 1899, p. 939.

[387] Only one of the two internal carotid arteries is shown in Fig. 199.

[388] J. Müller, _U. d. Bau u. d. Grenzen d. Ganoiden_, Berlin, 1846, p.
43; Ramsay Wright, _Standard Nat. Hist_. iii. pp. 48, 49.

[389] Baldwin Spencer, _Macleay Memorial Volume_, 1892, p. 1.

[390] Newton Parker, _Trans. Roy. Irish Acad_. xxx. 1892, p. 173.

[391] According to Boas; for reference, _see_ p. 329.

[392] This structure may prove to be a hemibranch of the first branchial
arch.

[393] Newton Parker, _op. cit_. p. 167.

[394] Newton Parker, _op. cit_. p. 138.

[395] De Meuron, _Recherches sur le développement du Thymus et de la glande
thyreoïde_, Inaug. Dissert. Genève, 1886; Maurer, _Morph. Jahrb_. xi.
1886, p. 129; W. Müller, _Jen. Zeitsch_. vi. 1871, p. 428; vii. 1873,
p. 327; Dohrn, _Mitth. Zool. Stat. Neapel_, vi. 1886, p. 49; vii.
1887, p. 301.

[396] _Cf_. p. 280.

[397] Newton Parker, _op. cit_. p. 135.

[398] Quoted by N. Parker, _l.c._

[399] Van Bemmelen, _Anat. Anz_. iv. 1889, p. 400.

[400] W. Müller, _op. cit_.

[401] Dohrn, _Mitth. Zool. Stat. Neapel_. v. 1884, pp. 141-151; see also
the previously cited works of De Meuron and Maurer.

[402] Dohrn, _op. cit_.

[403] See pp. 120 and 135. Willey, _Amphioxus and the Ancestry of the
Vertebrates_, New York, 1894, pp. 30, 31.

[404] Beard, _Anat. Anz_. ix. 1894, p. 485.

[405] Newton Parker, _op. cit_. p. 135.

[406] Giacomini, quoted by Swale Vincent, _Journ. Anat. and Phys_. xxxviii.
1903, p. 41.

[407] Vincent, _Trans. Zool. Soc_. xiv. Part iii. 1897, p. 41. For
bibliography see Vincent, _Internat. Monatsschr. f. Anat. u. Phys_.
xv. 1898, p. 319.

[408] Giacomini, quoted by Swale Vincent, _Journ. Anat. and Phys_. xxxviii.
1903, p. 41.

[409] Vincent, _op. cit_. pp. 32, 33.

[410] Balfour, _Quart. J. Micr. Sci_. xxii. 1882, p. 12.

[411] Swale Vincent, _op. cit_. p. 78.

[412] _Ibid_. pp. 77, 78.

[413] Balfour, _op. cit_. p. 16.

[414] See Chapter XI.

[415] Pettigrew, _Animal Locomotion_, Internat. Sci. Series, London, 1874,
p. 64; Gadow, _Science for All_ (Cassell), v. p. 302.

[416] Bridge, _Journ. Linn. Soc. (Zool.)_, xxv. 1896, p. 530.

[417] Sörensen, _Om Lydorganer hos Fiske_, Copenhagen, 1884; Dufossé, _Ann.
d. Sci. Nat_. Ser. 5, xix. Art. 5, 1874, and xx. Art. 3, 1874. For
references to earlier papers see Sörensen, _op. cit_.

[418] Haddon, _Journ. Anat. and Phys_. xv. 1881, p. 322; Bridge and Haddon,
_Phil. Trans_. 184, 1893, p. 168.

[419] Möbius, _Sitz. d. Berlin. Akad. d. Wiss_. 1889, p. 999.

[420] _Notes by a Naturalist on H.M.S. "Challenger,"_ London, 1879, p. 51.

[421] The elastic-spring-mechanism has been described by several writers,
who had assigned to it various functions, but Sörensen (_op. cit_.
pp. 85-91) was the first to discover its vocal function by
observations and experiments on _Doras maculatus_.

[422] The mechanism is apparently absent in one species of _Pangasius_ (_P.
micronema_). Bridge and Haddon, _op. cit_. p. 220.

[423] Moreau, _Compt. Rendus_, lix. 1864, p. 436; _Ann. d. Sci. Nat_. (6)
iv. 1876, p. 65.

[424] Sörensen, _Lydorganer_, p. 82, _et. seq_.

[425] Cf. Mettenheimer, _Arch. f. Anat. u. Physiol_. 1858, p. 302.

[426] Günther, _Phil. Trans_. 161, 1871, p. 542.

[427] Pappe, _Synopsis of the Edible Fishes at the Cape of Good Hope_,
Capetown, 1853, p. 8.

[428] Günther, _Study of Fishes_, Edinburgh, 1880, p. 427.

[429] Day, _Fishes of Great Britain and Ireland_, London, i. 1880-1884, p.
151.

[430] Sörensen, _op. cit_.

[431] Moreau, _op. cit_.

[432] Ewart, _Phil. Trans_. 179 (B), 1888, pp. 399, 410, and 539; 183 (B),
1893, p. 389.

[433] Ballowitz, _Arch. Mikr. Anat_. l. 1897, p. 686; Carl Sachs,
_Untersuchungen am Zitteraal_, Leipzig, 1881.

[434] Ballowitz, _Das Electrische Organ des Africanischen Zitterwelses_,
Jena, 1899.

[435] Gotch, _Phil. Trans_. 178, 1888, p. 487.

[436] Id. _op. cit_. p. 535.

[437] Cf. p. 580.

[438] Graham Kerr, _Quart. Journ. Micr. Sci_. xlvi. 1902, p. 417.

[439] For the nomenclature of the brain and its cavities see T. J. Parker,
_Nature_, xxxv. 1886, p 208; and Parker and Haswell, _Text-Book of
Zoology_, London, 1897, ii. p. 94.

[440] It is possible that the prosencephalon is merely the bulging anterior
part of the thalamencephalon; if this be so the hemispheres are
really paired outgrowths from the thalamencephalon.

[441] In Lizards _either_ of the two vesicles may become a parietal eye
(Dendy, _Quart. Journ. Micr. Sci_. xlii. 1899, p. 111).

[442] Holm, _Morph. Jahrb_. xxix. 1901, p. 365.

[443] The sacci probably secrete the fluid contents of the ventricles.

[444] Haller, _Morph. Jahrb_. xxvi. 1898, p. 345.

[445] Goronowitsch, _Morph. Jahrb_. xiii. 1888, p. 427.

[446] Burckhardt, _Das Central-Nervensystem v. Protopterus annectens_.
Berlin, 1892.

[447] Sanders, _Ann. Nat. Hist_. (6) iii. 1889, p. 157.

[448] See Gaskell's important paper, _Journ. Physiol_. vii. 1886, p. 1.

[449] Herrick, _Journ. Neur_. ix. p. 153; Cole, _Trans. Roy. Soc. Edinb_.
xxxviii. 1896, p. 631; Id. _Trans. Linn. Soc_. vii. 1898, p. 115, to
which an excellent bibliography is appended.

[450] For a discussion of the relations of "end-buds" to the sense of taste
in Fishes, see Bateson, _Journ. Marine Biol. Ass_. i. (N.S.) 1890, p.
225; and Herrick, _U.S. Fish Commiss. Bull_. 1902, p. 237. In the
latter paper a bibliography of the subject is given.

[451] These fibres are included in the visceral sensory or "communis"
system by Herrick.

[452] See previously cited papers by Herrick and Cole; also Ewart, _Trans.
Roy. Soc. Edinb_. xxxvi. 1892, p. 59; Collinge, _Quart. Journ. Micr.
Sci_. xxxvi. 1894, p. 499; and Herrick, _Journ. Comp. Neurology_, xi.
1901, p. 177.

[453] Allis, _Journ. Morph_. ii. 1889, p. 463.

[454] Johnston, _Journ. Comp. Neurology_, xii. 1902, p. 2.

[455] Fuchs (_Archiv f. d. ges. Physiol_. lix. 1895, p. 454) has suggested
that these organs may be concerned with the perception of pressure
variations. It has also been argued that they are concerned with
equilibration and the co-ordination of the movements of the fins.
(See _American Journ. Physiol_. i. p. 128.)

[456] Burckhardt, _Das Central-Nervensystem v. Protopterus_, Berlin, 1892,
p. 32.

[457] Bridge, _Journ. Linn. Soc_. xxvii. 1900, p. 503.

[458] Ridewood, _Journ. Anat. and Phys_. xxvi. 1892, p. 26.

[459] E. H. Weber, _De aure et auditu Hominis et Animalium_. Pars i. _De
aure Animalium Aquatilium_, Leipzig, 1820; Bridge and Haddon, _Phil.
Trans_. 184, 1893, p. 65.

[460] Sagemehl, _Morph. Jahrb_. x. 1885, p. 22.

[461] The Weberian ossicles are modified components of certain of the
anterior vertebrae. The scaphium represents the neural arch of the
first vertebra; the intercalarium is the arch of the second vertebra;
while the tripus is probably the rib of the third vertebra. In the
Characinidae and the Cyprinidae an additional ossicle, the
"claustrum" is present.

[462] See also Sörensen, _Journ. Anat. and Phys_. xxix. 1895, p. 399; and
Bridge, _Journ. Linn. Soc_. xxvii. 1900, p. 531.

[463] Bridge and Haddon, _op. cit_. p. 261.

[464] Id. _Proc. Roy. Soc_. lii. 1892, p. 139.

[465] Kupffer, _Stud. vergl. Entwickl. d. Kopfes d. Kraniaten_, iii. 1895,
p. 6.

[466] In _Bdellostoma_ the olfactory organ arises as a _pair_ of outgrowths
from the pituitary involution (Bashford Dean, Kupffer's
_Festschrift_, Jena, 1899, p. 269).

[467] Kyle, _Journ. Linn. Soc. (Zool.)_, xxvii. 1900, p. 541.

[468] Beer, _Wien. klin. Wochenschr_., No. xlii. 1898, p. 11.

[469] Chun, _Aus den Tiefen des Weltmeeres_, Jena, 1900, p. 534.

[470] Ritter, _Bull. Mus. Comp. Zool_. xxiv. 1893, p. 51.

[471] Eigenmann, _Arch. f. Entwickelungsmech_. viii. 1899, p. 545.

[472] Studnička, _Sitzber. k. böhm. Ges. Wiss_., 1899, No. xxxvii.

[473] Chun, _loc. cit_. p. 536.

[474] It is probable that the archinephric duct is derived from the
embryonic epiblast; hence the suggestion that in the primitive
Vertebrates the duct was a longitudinal groove in the superficial
skin into which the pronephric tubules opened externally.

[475] W. Müller, _Jen. Zeitsch_. ix. 1875, p. 107; Semon, _Carl Gegenbaur's
Festschrift_, Leipzig, 1896, iii. p. 169.

[476] Jungersen, _Zool. Anz_. xxiii. 1900, p. 328.

[477] Bridge, _Journ. Anat. and Phys_. xiv. 1879, p. 81; Bles, _ib_. xxxii.
1898, p. 484; _Proc. Roy. Soc_. lxii. 1898, p. 232.

[478] Max Weber, _Morph. Jahrb_. xii. 1886, p. 336.

[479] Ewart, _Journ. Anat. and Phys_. x. 1876, p. 488.

[480] Burne, _Linn. Soc. Journ. Zool_. xxvi. 1898, p. 487.

[481] Semper, _Centralblatt f. Med. Wiss_. 1875, No. 29; F. M. Balfour,
_Journ. Anat. and Phys_. x. 1875, p. 17; Id. _Comparative
Embryology_, London, 1881, ii. p. 568.

[482] Huxley, _P.Z.S._ 1883, p. 132.

[483] Budgett, _Trans. Zool. Soc_. xv. 1901, p. 323; xvi. 1902, p. 315.

[484] Graham Kerr, _P.Z.S._ 1901, p. 484; _Proc. Phil. Soc. Cambridge_, xi.
Pt. v. 1902, p. 329.

[485] Graham Kerr, _op. cit_.

[486] Hirota, _Journ. Coll. Sci. Imp. Univ. Japan_, vii. 1895, p. 367.

[487] For the eggs of Cyclostomes see Chapter XVI.

[488] For a description of the eggs and breeding habits, and the larval
development and migrations of British Marine Fishes, see M‘Intosh and
Prince, _Trans. Roy. Soc. Edin_. 1890; M‘Intosh, _Ann. Report Fishery
Board for Scotland_, 1892; Cunningham, _Marketable Marine Fishes of
the British Islands_, London, 1896; M‘Intosh and Masterman,
_Life-Histories of the British Marine Food-Fishes_, London, 1897;
also numerous papers by Cunningham, Holt, Garstang, and Allen, in the
_Journ. Marine Biol. Assoc. Plymouth_, vols. i.-vi.

[489] See Chapter XVII.

[490] Cunningham, _op. cit_. p. 69.

[491] Guitel, _Arch. Zool. Expér. et Gén_. (3), i. 1893, p. 611.

[492] Garman, _Mem. Mus. Comp. Zool_. xix. 1895, No. 1, p. 11.

[493] Cunningham, _op. cit_. p. 358.

[494] H. v. Jhering, _Zeitschr. wiss. Zool_. xxxviii. 1883, p. 468.

[495] See p. 592.

[496] Olt, _Zeitschr. wiss. Zool_. lv. 1893, p. 643.

[497] _Cf_. p. 584.

[498] Budgett, _Trans. Zool. Soc_. xvi. Pt. ii. 1901, p. 130.

[499] See Chap. XVII. p. 434.

[500] Eigenmann, _Bull. Fish Comm_. (U.S.), 1892, p. 381; _Arch.
Entwickelungsmech_. iv. 1896, p. 125; Cunningham, _op. cit_. p. 356,
_et seq_.

[501] For a general account of Sexual Dimorphism in Fishes, see
Cunningham's _Sexual Dimorphism in the Animal Kingdom_, London, 1900,
pp. 178-227. Some of the more striking examples of Sexual Dimorphism
are mentioned in the chapters dealing with the different families of
Fishes.

[502] Holt, "On the Breeding of the Dragonet (_Callionymus lyra_),"
_P.Z.S._ 1898, p. 281.

[503] Howes, _Linn. Soc. Journ. Zool_. xxiii. 1891, p. 539, where
references are given to the literature of the subject.

[504] The American Hags probably belong to a distinct species, _M. limosa_
Girard; Bashford Dean, _Science_ (N.S.), xvii. 1903, p. 433.

[505] Bashford Dean, Kupffer's "_Festschrift_," Jena, 1809, p. 227 _et
seq_.

[506] _Journ. Morph_. xvii. 1898, p. 213.

[507] Jordan and Evermann, _Bull. U.S. Nat. Mus_. No. 47; _The Fishes of
North and Middle America_, Pt. i. 1896, p. 6.

[508] B. Dean, _op. cit_. p. 230 _et seq_.

[509] Jordan and Evermann, _op. cit_. p. 9 _et seq_.

[510] Plate, _Sitzungsb. d. Gesellsch. Naturforsch. Freunde Berlin_, No. 8,
1897, p. 137.

[511] Bashford Dean and F. B. Sumner, _Trans. N. Y. Acad. Sci_. xvi. 1897,
p. 321.

[512] Dohrn, _Mitth. Zool. Stat. Neapel_, vi. 1886, p. 59; Shipley, _Quart.
Journ. Microsc. Sci_. xxvii. 1887, p. 325.

[513] R. Alcock, _Journ. Anat. and Phys_. xiii. (N.S.), 1899, p. 623.

[514] Day, _Fishes of Great Britain and Ireland_, Lond. ii. 1880-84, p.
360.

[515] _Den Danske Ingolf-Expedition_, ii. No. 2, Copenhagen, 1898.

[516] Cunningham, _Marketable Marine Fishes_, London, 1896, p. 64.

[517] Wood-Mason and Alcock, _Proc. Roy. Soc_. 49, 1891, p. 359.

[518] Leydig, _Mikrosk. Anat. u. Entwick. d. Rochen u. Haie_, Leipzig,
1852, p. 90 _et seq_.

[519] T. J. Parker, _Trans. New Zealand Instit_. xxii. 1889 (1890), p. 331.

[520] Smith Woodward, _Vertebrate Palaeontology_, Cambridge, 1898, p. 32.

[521] B. Dean, _Journ. Morph_. ix. 1894, p. 87. _Trans. New York Acad.
Sci_. xiii. 1894, p. 115.

[522] Traquair, _Geol. Mag_. (3), v. 1888, p. 81; _Trans. Geol. Soc.
Glasgow_, xi. 1897, p. 41.

[523] For references see Zittel's _Text-Book of Palaeontology_ (Eng. trans.
ed. by C. R. Eastman), London and New York, ii. 1902, pp. 22-23.

[524] See also restoration of _Pleuracanthus gaudryi_ from the
Coal-Measures of Commentry, Allier, France, by C. Brongniart; Zittel,
_op. cit_. p. 23.

[525] A. Fritsch, _Fauna der Gaskohle in Böhmen_, ii. Prague, 1889; Kner,
_SB. Akad. Wiss. Wien Math.-Naturw. Cl_. lvii. Pt. i. 1868, p. 290;
Traquair, _Geol. Mag_. (3), v. 1888, p. 511, and (4) i. 1894, p. 254.

[526] Günther, _Study of Fishes_, Edin. 1880; _British Mus. Cat. Fishes_,
viii. 1870; Müller and Henle, _Syst. Beschr. d. Plagiost_. Berlin,
1841. Hasse, _Natürl. Syst. d. Elasmobr_. Jena, 1879. Goode and Bean,
_Oceanic Ichthyology_, Washington, 1895. Jordan and Evermann, _Fishes
of North and Middle America_, Washington, 1896, Pt. i. Smith
Woodward, _Vertebrate Palaeontology_, Cambridge, 1898; id. _Brit.
Mus. Cat. Foss. Fishes_, i. 1889, ii. 1891; Zittel, _op. cit_.

[527] Garman, _Bull. Mus. Comp. Zool. Harvard_, xii. No. 1, 1885, p. 1;
Günther, _Chall. Rep. Zool_. xxii. 1887, p. 2.

[528] Smith Woodward, _Nat. Science_, i. 1892, p. 671.

[529] Günther, _Study of Fishes_, p. 328.

[530] Goode and Bean, _op. cit_. p. 23.

[531] Müller and Henle, _op. cit_.

[532] Boulenger, _Ann. Mag. Nat. Hist_. (7), x. 1902, p. 51.

[533] Day, _British Fishes_, London, 1880-84, ii. p. 294.

[534] Cantor, quoted by Günther, _op. cit_. p. 318.

[535] T. J. Parker, _P.Z.S._ 1887, p. 27.

[536] D. S. Jordan, _California Acad. Sci_. (3), _Zool_. i. 1898; Bashford
Dean, _Science_ (N.S.), xvii. 1903, p. 630.

[537] Smith Woodward, _Ann. Mag. Nat. Hist_. (7), iii. 1899, p. 487.

[538] Kershaw, _Victorian Natural_. xix. 1901, p. 62; Waite, _Rec. Austral.
Mus_. iv. 1901, p. 263.

[539] Alcock, _Ann. Mag. Nat. Hist_. (6), iv. 1889, p. 379.

[540] Day, _op. cit_. p. 324. See also Stead, _Journ. Mar. Biol. Ass_. iv.
1895-97, p. 264.

[541] _Vertebrate Palaeontology_, Cambridge, 1898, p. 32.

[542] I am indebted to Mr. Boulenger for these observations.

[543] Alcock, _Ann. Mag. Nat. Hist_. (6), iv. 1889, p. 380.

[544] Jordan and Evermann, _op. cit_. p. 76.

[545] Day, _op. cit_. p. 336.

[546] Zittel, _op. cit_. p. 41.

[547] Jordan and Evermann, _op. cit_. p. 85.

[548] Günther, _op. cit_. p. 348.

[549] Duméril, quoted by Jordan and Evermann, _op. cit_. p. 92.

[550] Rohon, _Verhandl. k. Min. Ges. Petersburg_, xxxiii. 1895, p. 1.

[551] Smith Woodward, _Proc. Zool. Soc_. 1886, p. 527; and 1887, p. 481.

[552] Id., _Ann. Mag. Nat. Hist_. iv. (6), 1889, p. 275.

[553] Günther, _Ann. Mag. Nat. Hist_. (6) iv. 1889, p. 415.

[554] See also an account of the egg-case of a Chimaeroid dredged from a
depth of 516 fathoms in the Bay of Bengal (Wood-Mason and Alcock,
_Ann. Mag. Nat. Hist_. (6) viii. 1891, p. 21).

[555] Goode and Bean, _op. cit_. p. 32.

[556] Mitsukuri, _Zool. Mag. Tokyo_, 1895, quoted in _Nat. Sci_. viii.
1896, p. 10.

[557] Günther, _Chall. Reports, Zool_. xxii. 1887, p. 12.

[558] Bashford Dean, _Mem. New York Acad. Sci_. ii. Pt. i. 1899, p. 28;
_Biol. Bull_. iv. 1903, p. 270.

[559] E. T. Newton, _Mem. Geol. Surv. Monogr_. iv. 1878; Riess,
_Palaeontogr_. xxxiv. 1887, p. 1; Smith Woodward, _Brit. Mus. Cat.
Foss. Fishes_, ii. 1891, p. 52; Zittel, _Text-Book of Palaeontology_,
English ed., London and New York, ii. 1902, p. 46.

[560] Hence the name "Teleostomi" or "perfect-mouthed" Fishes.

[561] Boulenger, _Poissons du Bassin du Congo_, Bruxelles, 1901, p. 2.
Smith Woodward (_Brit. Mus. Cat. Foss. Fishes_, ii. 1891, p. 317; and
_Vert. Palaeont_. Cambridge, 1898, p. 78), following Cope, recognises
four sub-orders, the Haplistia, Rhipidistia, Actinistia, and
Cladistia. The first sub-order is reserved for the Tarrasiidae, a
family which includes only the little known _Tarrasius problematicus_
from the Lower Carboniferous of Scotland.

[562] Traquair, _Trans. Roy. Soc. Edinb_. xxvii. 1875, p. 383.

[563] Whiteaves, _Trans. Roy. Soc. Canada_, vi. 1888, p. 77.

[564] Traquair, _Trans. Roy. Soc. Edinb_. xxx. 1881, p. 169.

[565] Traquair, _Proc. Roy. Soc. Edinb_. xvii. p. 388.

[566] Reiss, Die Coelacanthinen, _Palaeontogr_. xxxi. 1888, p. 1; Smith
Woodward, _Brit. Mus. Cat. Foss. Fishes_, ii. 1891, p. 394.

[567] See also _Kurtus indicus_, p. 688.

[568] Smith Woodward, _op. cit_. p. 412.

[569] Boulenger, _Poiss. Bass. Congo_, p. 10. For a list of the more
important papers, see pp. 18-19 of that work.

[570] Mr. Boulenger informs me that he regards these spines as modified
ridge scales or fulcra. The latter are median spine-like or Λ-shaped
scales in relation with the anterior margins of the median fins in
some Crossopterygii (_e.g._ Osteolepidae) and in many Chondrostei and
Holostei.

[571] Boulenger, _op. cit_. p. 20 _et seq_.; id. _Ann. Mus. Congo, Zool_.
(1), i. Fasc. 4, Bruxelles, 1899, p. 61; ii. Fasc. 2, 1902, p. 23.

[572] _Proc. Camb. Phil. Soc_. x. 1900, p. 236; _Trans. Zool. Soc_. xvi.
Pt. ii. 1901, p. 115.

[573] _Amer. Nat_. xxxiii. 1899, p. 721; _Science_ (2), ix. 1899, p. 314.

[574] Budgett, _Trans. Zool. Soc_. xv. Pt. vii. 1901, p. 330.

[575] _Trans. Zool. Soc_. xvi. Pt. ii. 1901, p. 118; also footnote on p.
317.

[576] p. 290.

[577] Traquair, _Journ. Geol. Soc. Ireland_ (2), 1871, p. 249.

[578] Boulenger, _Les Poissons du Bassin du Congo_, Bruxelles, 1901, p. 27.

[579] Traquair, _Monogr. Palaeont. Soc. 1877_; _Quart. Journ. Geol. Soc_.
xxxiii. 1877; _Trans. Roy. Soc. Edinb_. xxx. 1883, p. 22; _Ann. Mag.
Nat. Hist_. (4) xv. 1875, p. 237; Smith Woodward, _Mem. Geol. Surv.
N. S. Wales, Palaeont_. No. 4, 1890, and No. 9, 1895.

[580] Traquair, _Trans. Roy. Soc. Edinb_. xxix. 1879, p. 343.

[581] Smith Woodward, _Brit. Mus. Cat. Foss. Fishes_, iii. 1875, p. 7.

[582] Traquair, _Geol. Mag_. (3) iv. 1887, p. 248; Smith Woodward, _Brit.
Mus. Cat. Foss. Fishes_, iii. 1895, p. 23.

[583] Jordan and Evermann, "Fishes of North and Middle America," _Bull.
U.S. Nat. Mus_. No. 47, Pt. i. 1896, p. 101.

[584] Jordan and Evermann, _op. cit_. p. 102.

[585] Day, _Fishes of Great Britain and Ireland_, ii. 1880-84, p. 282.

[586] Id., _op. cit_. p. 279.

[587] _Brit. Mus. Cat. Foss. Fishes_, iii. pp. 48, 415.

[588] Bashford Dean, _Q.J.M.S._ xxxviii. p. 413.

[589] This genus also occurs in the Cretaceous of Brazil (Smith Woodward,
_A.M.N.H._ (7) ix. 1902, p. 87.)

[590] It is possible that a similar articulation is present in _Lepidotus_
(Smith Woodward, _Brit. Mus. Cat. Foss. Fishes_, iii. p. 79).

[591] Jordan and Evermann, _op. cit_. p. 108, _et seq_.

[592] Alex. Agassiz, _Proc. Amer. Acad. Arts and Sc_. xiii. 1878, p. 65;
Mark, _Bull. Mus. Comp. Zool. Harvard_, xix. 1890, p. 1.

[593] Mark, _op. cit_. p. 3.

[594] Pander, _Ueber die Ctenodipterinen des Devonischen Systems_, St.
Petersb. 1858.

[595] Traquair, _Ann. Mag. Nat. Hist_. (5), ii. 1878, p. 1; _Geol. Mag_.
(3), vi. 1889, p. 97; Smith Woodward, _Brit. Mus. Cat. Foss. Fishes_,
ii. 1891, p. 235 _et seq_.

[596] Traquair, _Journ. Roy. Geol. Soc. Ireland_ (N.S.), iii. 1873, p. 41;
_Proc. Roy. Soc. Edinb_. xvii. 1890, p. 393.

[597] Kner, _SB. k. Akad. Wiss. Math.-Naturw. Cl_. lvii. Pt. ii. 1868, p.
279.

[598] See Chaps. XI. XII. and XIV.

[599] Miall, _Palaeont. Soc_. 1878; Teller, "Ueber Ceratodus sturi," _Abh.
k. k. Geol. Reichsanst_. Wien. xv. 1891.

[600] Günther, _Phil. Trans_. 161, 1871, p. 511.

[601] Semon, _Zool. Forsch. im Australien_, i. Jena, 1893, p. 13 _et seq_.

[602] Semon, _op. cit_. p. 115.

[603] For a list of the more important papers on _Protopterus_, see
Boulenger, _Les Poissons du Bassin du Congo_, Bruxelles, 1901, pp.
40-42.

[604] Traquair, _Rep. Brit. Ass_. 1871 (2), p. 143; Boulenger, _P.Z.S._
1891, p. 147.

[605] Newton Parker, _Trans. Roy. Irish Acad_. xxx. 1892, p. 201.

[606] _Trans. Zool. Soc_. xvi. Pt. ii. 1901, p. 119.

[607] Bohls, _Gött. Nachrichten_, 1894, p. 84; Lankester, _Trans. Zool.
Soc_. xiv. Pt. i. 1896, p. 11; Goeldi, xiv. Pt. vii. 1898, p. 413;
Graham Kerr, _Phil. Trans_. (B), 192, 1900, p. 299.

[608] Hunt, _P.Z.S._ 1898, p. 41.

[609] Lankester, _Nature_, 49, 1894, p. 555; id. _Trans. Zool. Soc_. xiv.
Pt. i. 1896; Graham Kerr, _op. cit_. p. 306.

[610] For further information about the development of _Lepidosiren_, see
Graham Kerr's valuable paper, _op. cit_.

[611] Dollo, _Sur la Phylogénie des Dipneustes_, Bruxelles, 1895.

[612] For critical remarks, see Traquair, _Brit. Ass. Reports_, 1900, p.
776 _et seq_.

[613] Compare Figs. 301 and 304.

[614] It is worthy of note that _Protopterus dolloi_ approaches
_Lepidosiren_ in the more Eel-like shape of its body, and in the
large number of pairs of ribs (54) which it possesses (Boulenger,
_op. cit_. p. 37).

[615] Traquair, _Ann. Nat. Hist_. (6) vi. 1890, p. 485; _Proc. Roy. Phys.
Soc. Edinb_. xii. 1893, p. 87; _ibid_. p. 312; _P.Z.S._ 1897, p. 314;
Bashford Dean, _Trans. New York Acad. Sci_. xv. 1896, p. 101; _Mem.
New York Acad. Sci_. ii. 1900, p. 1.

[616] In a recently published and important contribution to our knowledge
of _Palaeospondylus_, by Professor and Miss Sollas (_Phil. Trans_.
196, 1903, p. 343), they describe structures on the ventral surface
of the head, which they maintain to be branchial arches, as well as
others which, in their view, may represent hyomandibular and
mandibular elements.

[617] Graham Kerr, _Proc. Camb. Phil. Soc_. x. 1900, p. 298.

[618] Lankester, _Nat. Sci_. xi. 1897, p. 45.

[619] Traquair, _Trans. Roy. Soc. Edinb_. xxxix. 1899, pp. 595 and 828.

[620] Id. _Trans. Roy. Soc. Edinb_. xxxix. 1899, p. 844; _Geol. Mag_. vii.
1900, p. 153; ix. 1902, p. 289; _Trans. Roy. Soc. Edinb_. xl. Pt. iv.
1903, p. 723.

[621] Lankester, _Monogr. Palaeont. Soc_. 1868, 1870; _Geol. Mag_. x. 1873,
p. 241; Smith Woodward, _Brit. Mus. Cat. Foss. Fishes_, ii. 1891, p.
159.

[622] Traquair, _Trans. Roy. Soc. Edinb_. xxxix. 1899, p. 834.

[623] Lankester, _Monogr. Palaeont. Soc_. 1868 and 1870; Smith Woodward,
_Brit. Mus. Cat. Foss. Fishes_, ii. 1891, p. 176.

[624] Traquair, _Proc. Roy. Phys. Soc. Edinb_. xii. 1894, p. 269.

[625] _Trans. Roy. Soc. Edinb_. xxxix. p. 843 _et seq_.; _Rep. Brit. Ass_.
1900, p. 768.

[626] See critical remarks by Smith Woodward, _Geol. Mag_. vii. 1900, p.
66.

[627] Lankester, _Nat. Sci_. xi. 1897, p. 46.

[628] Traquair, _op. cit_. p. 837.

[629] Smith Woodward, _Ann. Nat. Hist_. (7), v. 1900, p. 416.

[630] Traquair, _Monogr. Palaeont_. Soc. 1894.

[631] Traquair, _Ann. Nat. Hist_. (6), ii. 1888, p. 485.

[632] Traquair, _Proc. Roy. Phys. Soc. Edinb_. xi. 1891-92, p. 283.

[633] Traquair, _Ann. Nat. Hist_. (6), v. 1890, p. 125.

[634] Traquair, _Geol. Mag_. (3), vii. 1890, p. 55; _Proc. Roy. Phys. Soc.
Edinb_. x. p. 227.

[635] Id. _Geol. Mag_. (3), vi. 1889, p. 1.

[636] Newberry, _The Palaeozoic Fishes of North America, Mon. U.S. Geol.
Survey_, xvi. 1889; Bashford Dean, _Fishes, Living and Fossil_, New
York, 1895, p. 129 _et seq_.; _New York Acad. Sci. Mem_. ii. 1901, p.
87; Eastman, _Amer. Journ. Sci_. (4), ii. 1896, p. 46; _Amer. Geol_.
xviii. 1896, p. 222; _Bull. Mus. Comp. Zool_. xxxi. 1897, p. 19.

[637] _Rept. Brit. Assoc_. 1900, p. 779.

[638] The natural position of the Teleostei in the series of Fishes is
indicated on p. 149.

[639] This exists in _Dapedius_, as pointed out by A. S. Woodward. But this
genus should certainly be removed from the vicinity of _Lepidotus_,
and it seems to bear affinity with the Pholidophoridae.

[640] A synopsis of the classification followed in this work has been
published in the _Annals and Magazine of Natural History_ (7), xiii.
1904, p. 161. Some corrections have been introduced, chiefly due to
the investigations of Dr. W. G. Ridewood.

[641] See p. 553, Fig. 333, B.

[642] Cf. Boas, _Morph. Jahrb_. vi. 1880, p. 527, who has found the conus,
but in a still more rudimentary condition, and with a single row of
valvules, in _Heterotis_ and _Notopterus_ also.

[643] For a general account of the Fishes of this family, cf. Boulenger,
_P.Z.S._ 1898, p. 775, and _Poissons du Bassin du Congo_, p. 49
(1901), where a bibliographical index to the principal anatomical and
physiological publications will be found.

[644] _Trans. Zool. Soc_. xvi. 1901, p. 126.

[645] _Journ. Linn. Soc_. xxvii. 1900, p. 503.

[646] On the Anatomy, cf. Agassiz, in Spix, "Pisc. Brasil." p. 32; Hyrtl,
_Denkschr. Ak. Wien_, viii. 1855, p. 73; Hemprich and Ehrenberg,
"Symb. Phys." Zootom. pls. viii. and ix.; Bridge, _P.Z.S._ 1895, p.
302.

[647] I have not been able to convince myself of the existence of an
intergular plate in this genus, but I am satisfied that the
postclavicle rests on the outer side of the clavicular arch. The bone
that has been regarded as a small intergular plate in _Spaniodon_ is,
in my opinion, the glossohyal.

[648] On the life-histories of the British Clupeids, cf. Heincke,
"Naturgeschichte des Herings" (_Abh. Deutsch. Seefisch. Ver_. ii.
1898); J. T. Cunningham, "Life-History of the Pilchard" (_J. Mar.
Biol. Ass_. [2] iii. 1894, p. 148), and the manuals of the latter
author (_Marketable Fishes of Great Britain_, 1896) and of M‘Intosh
and Masterman (_British Marine Food-Fishes_, 1897).

On the accessory branchial organs of some genera, see p. 294.

[649] For important contributions to our knowledge of European and American
Salmonids since the publication of Günther's account in the British
Museum Catalogue, cf. F. Day, _British and Irish Salmonidae_ (1887),
Smitt, _Krit. Förteckn. Riksmus. Salmonider_ (1886), Fatio, _Faune
des Vertébrés de la Suisse_, v. (1890), and Jordan and Evermann,
_Fish. N. America_, i. (1896).

[650] In _Anomalopterus_, however, a sort of adipose fin exists, as a fold
or cushion on the back, but _in front_ of the rayed dorsal.

[651] A detailed description of the skull of _Alepocephalus rostratus_ has
been given by Gegenbaur, _Morphol. Jahrb_. iv. Suppl. 1878, p. 1.

[652] As pointed out by Gegenbaur. These forms are, however, placed by Gill
in a division characterised by the atrophy or absence of the
mesocoracoid.

[653] See above, p. 178.

[654] _Zool. Jahrb. Anat_. xviii. 1903, p. 58.

[655] _Morphol. Jahrb_. x. 1885, p. 22.

[656] For the nomenclature of these ossicles, cf. Bridge and Haddon, _Proc.
Roy. Soc_. xlvi. 1889, p. 310.

[657] On the anatomy of the Characinidae, cf. Sagemehl, _Morphol. Jahrb_.
x. 1885, p. 102, and xii. 1887, p. 307, and Rowntree, _Tr. Linn.
Soc_. ix. 1903, p. 247.

[658] The end of the tail, when injured, is easily reproduced. As in
Lizards, the axis of the regenerated part is an undivided calcified
tube.

[659] Cf. Reinhardt, _Arch. f. Naturg_. 1854, p. 159.