Chapter XXVIII: Introduction: General Characters and Terminology—brown Bodies—history (5)

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NOTES

[1] Hemprich and Ehrenberg, _Symbolae physicae_, Berlin, fol. 1831.

[2] Τρῆμα, a hole; referring to the orifices of the suckers.

[3] _Mémoires pour servir à l'histoire d. Polypes d'eau douce_, Leyden,
1744.

[4] _Die Parasiten des Menschen_, 1879——. Engl. Transl. by W. E. Hoyle,
i. 1886.

[5] Band 4, by M. Braun. (Mesozoa and Trematoda completed; Cestoda in
progress.)

[6] _Verm. terr. et fluv. ... succincta historia_, 1773; _Zool. Danica_,
1777.

[7] _Observations on Planariae_, Edinburgh, 1813.

[8] M. Faraday, "On the Planariae," _Medical Gazette_, Feb. 1832; and in
_Edinburgh New Philosoph. Journal_, vol. xiv. 1833, pp. 183-189.

[9] _Nov. Act. Acad. Caes. Leop.-Carol._ tom. xiii. 1827.

[10] _Ann. Sci. Nat._ (Zool.) I. tom. xv. 1828.; _ibid._ tom. xxi. 1830.

[11] _Mém. Acad. St. Pétersbourg_, 5th ser. tom. ii. 1832.

[12] _Die rhabdocoelen Turbellarien des Süsswassers._ Jena 1848.

[13] _Monographie d. Turbellarien._ I. Rhabdocoelida, 1882. Die Acoela,
Leipzig, 1892.

[14] "Die Polycladen," _Fauna u. Flora d. Golfes v. Neapel_, Monogr. XI.
1884.

[15] _Phil. Trans._ 1874, p. 105.

[16] Since no food, but only the pharynx, passes through this "mouth," the
term is unfortunate. Moreover the true mouth is the aperture placing
the stomach in communication with the pharynx (Fig. 5, _gm_).

[17] _Ann. Sci. Nat._ 1 sér. tom. xv. 1828, p. 146. "La Planaire
trémellaire ... peut parcourir ... en faisant battre rapidement ses
parties latérales à la manière des larges nageoires des Raies."

[18] _Observations on Planariae._ Edinburgh, 1813, p. 12.

[19] "Zur Anat. u. Entwickl. einiger Seeplanarien v. St. Malo," _Abh. K.
Gesellschaft d. Wiss._ Göttingen, 1868.

[20] The roof of the peripharyngeal chamber is hence known as the
"diaphragm."

[21] See Brandt, _Fauna u. Flora d. Golfes v. Neapel_, Monogr. XIII. 1885,
p. 65.

[22] See p. 94.

[23] _Verhandlungen d. med. Gesellschaft zu Würzburg_, iv. 1854, p. 223.

[24] _Enantia spinifera_ Grff. _Mittheil. d. Naturwiss. Verein. f.
Steiermark_, 1889.

[25] The sucker of _Leptoplana tremellaris_ probably does not correspond
with that of the Cotylea.

[26] Collingwood, _Trans. Linn. Soc._ 2 ser. vol. i. pt. 3, 1876, p. 83.

[27] Von Stummer-Traunfels, _Zeitschr. f. wiss. Zool._ Bd. lx. 1895, p.
689.

[28] _Planocera pellucida_ Mertens, _P. simrothi_ v. Grff., _P. grubei_
Grff., _Stylochoplana sargassicola_ Mertens, _S. californica_
Woodworth, _Planctoplana challengeri_ Grff., all belonging to the
Planoceridae. See v. Graff, "Pelagische Polycladen," _Zeitschrift f.
wiss. Zoologie_, Bd. lv. 1892, p. 190.

[29] _Cambridge Natural History_, vol. iii. p. 74.

[30] Lang, "_Polycladen_," p. 629.

[31] Wheeler, _Journal of Morphology_, vol. ix. part 2, 1894, p. 195.

[32] Many Nudibranchiate Mollusca undergo this change of habitat. See
Garstang, _Journal of the Marine Biological Assoc._ n.s. i. No. 4,
1890, p. 447.

[33] Chun, "Ctenophoren," _Fauna u. Flora G. v. Neapel_, Monogr. I. 1880,
p. 180.

[34] See Lang, "_Polycladen_," p. 607.

[35] Lang, "_Polycladen_," Pl. 30, Fig. 8.

[36] _Kongl. Fysiograf. Sällskapets Handlingar_, Bd. iv. Lund, 1892-93.

[37] Whitman, _Journal of Morphology_, vol. iv. 1890, p. 361.

[38] A full account of Polyclad development is contained in Lang's
"_Polycladen_," with references to the literature of the subject.
Since the date of that work (1884) the embryology of Ctenophora has
become better known, but, though the segmentation of the egg and
early stages of development are very similar in both cases, the
elaborate investigations of E. B. Wilson (_Journ. Morphology_, vol.
vi. p. 361) show that the segmentation of Polychaet worms is again
similar. The question of the affinities of the Polycladida is also
discussed by Lang ("_Polycladen_" p. 642 _et seq._). The work of the
last decade has neither proved nor disproved his suggestion that the
Ctenophores and Polyclads have been derived from common ancestors. On
this subject the remarks made by Hatschek (_Lehrbuch d. Zoologie_, p.
319) are some of the weightiest that have appeared.

[39] Hallez, _Revue Biologique du Nord de la France_, tom. ii. 1889-90.

[40] Voigt, _Zool. Anz._ xv. p. 238.

[41] Grube, _Archiv f. Naturgeschichte_, 38 Jahrg. Bd. i. 1872, p. 273.

[42] Vejdovsky, _Zeitschr. f. wiss. Zoologie_, Bd. lx. 1895, p. 200.

[43] Woodworth, _Bulletin Mus. Comp. Zoology, Harvard_, vol. xxi. No. 1,
1891.

[44] _Mitth. Zool. Stat. Neapel_, 1882, p. 187.

[45] Wheeler, _Journal of Morphology_, vol. ix. 1894, p. 167.

[46] Dendy, _Trans. Roy. Soc. Victoria_ 1890, p. 65; Id. _Austral. Assoc.
Brisbane_, 1895, "Presid. Add. to Sect. D," p. 15.

[47] Darwin, _Ann. and Mag. Nat. Hist._ vol. xiv. 1844, p. 241.

[48] Shipley, _Proc. Camb. Phil. Soc._ vol. vii. pt. 4, 1891 (with
literature).

[49] _Trans. Roy. Soc. Victoria_ from 1889 onwards. _Trans. New Zealand
Institute_, 1894-95.

[50] Moseley, _Phil. Trans._ 1874, p. 105; Id. _Quart. Journ. Micr. Sci._
vol. xlvii. 1877, p. 273; Loman, _Bijdrag tot d. Dierkunde_, Aflev.
14, 1887, p. 71; Id. _Zool. Ergeb. ein. Reise in Nieder-Ost-Indien_,
Hft. 1, p. 131; Beddard, _Zoogeography_, 1895, p. 53.

[51] _Beobachtungen ü. Anat. u. Entwickel. an der Küste von Normandie_,
1863, p. 18.

[52] _Archiv f. Naturgeschichte_, 57 Jahrg. Bd. i. Hft. 3, 1891, p. 308.

[53] Dendy, _Proc. Roy. Soc. Victoria_, vol. iv. n.s. i. 1892.

[54] Schmarda, _Neue wirbellose Thiere_, Leipzig, 1859, I. i. p. 30.

[55] _Abhandl. d. Naturf. Gesell. zu Halle_, Bd. iv. 1857, p. 33.

[56] _Arb. Zool.-Zoot. Instit. Würzburg_, Bd. v. 1882, p. 120.

[57] Woodworth (_loc. cit._ p. 38) states that in _Phagocata_ the
yolk-glands arise by proliferation from two parovaria, placed just in
front of the ordinary ovaries. Iijima, however (_Zeitschr. f. wiss.
Zool._ Bd. xl. 1883, p. 454), regarded them as derivatives of the
parenchyma.

[58] The extensive literature on this subject is fairly completely
summarised by Voigt in _Biol. Centralblatt_, vol. xiv. Nos. 20, 21,
1894. Faraday's observations (cf. p. 6, note 8) have been generally
overlooked.

[59] _Archives d. Biologie_, tom. xii. 1892, p. 437.

[60] _Mitth. Zool. Stat. Neapel_, Bd. iii. 1882, p. 187.

[61] Böhmig, _Ergebnisse d. Plankton Expedition_, Bd. ii. H. g. 1895.

[62] von Graff, _Die Acoela_, Leipzig, 1892. Appendix.

[63] The development of the _Acoela_ has been worked out recently by
Mdlle. Pereyaslawzewa (_Zapiski Novoross. Obshch. Odessa_, 17 Bd.
1892) and Gardiner (_Journal of Morphology_, xi. No. 1, 1895, p. 155)
with conflicting results. The former finds four endoderm cells, which
give rise to a larval intestine. The _Acoela_ are for her,
_Pseudacoela_. Gardiner, on the other hand, finds no trace of an
endoderm at any stage of the development of _Polychoerus caudatus_.

[64] _Tijdschr. Nederland. Dierk. Ver._ Deel ii. 1875.

[65] Von Graff, _Monographie d. Turbellarien: I. Rhabdocoeliden_, 1882.
Gamble, _Quart. Journ. Microscop. Science_, vol. xxxiv. 1893, p. 433.

[66] _Zeitschr. f. wiss. Zoologie_, Bd. lx. 1895, p. 163.

[67] See von Graffs _Monographie_, pl. ix.; and Jensen, _Turbellaria ad
Litora Norvegiae_, Bergen, 1878, pl. iv.

[68] For the reproductive organs of Rhabdocoelida, consult von Graff,
_Monographie_, "Die Acoela"; and Böhmig, _Zeitschr. f. wiss. Zool._
Bd. li. 1891, p. 167.

[69] _Untersuchungen ü. Platyhelminthen_, Giessen, 1873, p. 101.

[70] Compare the remarks on Trematodes, pp. 4-5.

[71] Haswell, _Monograph of the Temnocephaleae_. Macleay Memorial Volume.
Mem. iii. 1893.

[72] Braun, in Bronn's _Klassen u. Ordn. d. Thierreichs_, vol. iv. p. 407,
gives a valuable summary of our knowledge of this group. For figures,
see van Beneden and Hesse, _Mémoires de l'Acad. roy. de Belgique_,
tom. xxxiv. 1864, pp. 1-169. A valuable paper (with synoptic tables)
on Japanese Monogenea, by Goto, _Journ. Coll. Sci. Japan_, vol. viii.
pt. 1, 1894, has recently appeared.

[73] See Leuckart, "_Parasiten_" Bd. ii. p. 238.

[74] Zeller, _Zeitschr. f. wiss. Zool._ xxii. 1872, pp. 1, 168; also Bd.
xxvii. 1876, p. 238; xlvi. 1888, p. 233.

[75] An excellent and beautifully illustrated account, by Looss, of the
Distomatidae of Frogs and Fishes may be found in Leuckart and Chun's
_Bibliotheca Zoologica_, Heft 16, 1894.

[76] Leuckart, _Parasiten d. Menschen_, "Trematoden," 1892-94; R.
Blanchard, _Traité d. Zool. médicale_, i. 1889; H. B. Ward, _Report
for 1894 of Nebraska State Board of Agric. Lincoln_, U.S.A. 1895, p.
225.

[77] Huxley, _Anat. of Invert. Animals_, 1877, p. 194.

[78] Braun, Bronn's _Thierreichs_, Bd. iv. p. 792; Leuckart, _Parasiten d.
Menschen_, 11 Abth. p. 158; Brandes, in _Spengels Zool. Jahrb. Syst.
Abtheil._ Bd. v. 1890, p. 849; v. Nordmann, _Mikr. Beitr._ i. Berlin,
1832.

[79] Heckert, _Bibliotheca Zoologica_ (Leuckart and Chun), Heft 4, 1889. I
am not aware that _Leucochloridium_ has been noticed in England.

[80] "Heterogamy" usually means the alternation of bisexual and unisexual
generations (e.g. _Rhabdonema nigrovenosum_), but is, unfortunately,
also used in the sense of Alloiogenesis, as defined above. See
Grobben, _Arbeit. Zool. zoot. Ints. Wien_, Bd. iv. 1881, p. 201.

[81] _Parasiten_, Bd. i. Abth. II. p. 152.

[82] _Festschrift f. Leuckart_, Leipzig, 1892, p. 167.

[83] _Quart. Journ. Micros. Sci._ vol. xxiii. 1883, p. 90.

[84] The intermediate host in the Sandwich Islands is said to be _Limnaea
peregra_. See Lutz, _Centralbl. f. Bakter._ xi. 1892, p. 783.

[85] The mortality in wet years, however, is said to be largely due to
pulmonary inflammation. This and other causes of death are not always
discriminated in the returns.

[86] See Thomas, _Quart. Journ. Micros. Science_, xxiii. 1883. Neumann,
_Parasites of Domesticated Animals_, translated by Fleming, 1892.

[87] Leuckart, _loc. cit._; Looss, _Archiv f. mikroskop. Anatomie_, Bd.
xlvi. 1895, p. 1.

[88] In Leuckart, _Die Parasiten d. Menschen_, pp. 521-528, 1894.

[89] Cf. p. 89.

[90] See Braun. Bronn's _Klassen u. Ordnungen d. Thierreichs_, vol. iv. p.
572.

[91] Braun, _loc. cit._ p. 573.

[92] Taken largely from Braun, _Ibid._ pp. 864-866, where the literature
of the subject is referred to fully.

[93] _Festschr. f. Leuckart_, 1892, p. 134.

[94] Cf. p. 5.

[95] _Arbeit. Inst. Wien_, iii. 1881, p. 163; see also _ibid._ ix. 1890,
p. 57.

[96] For figures of various scolices see van Beneden, _Mémoire sur les
vers Intestinaux_, 1861; Braun in Bronn's _Thierreich, Cestoda_ (in
progress), Bd. iv. Pl. xxxviii.-xlv.

[97] The mature proglottis of _Calliobothrium eschrichti_ is 8-9 mm. long,
whereas the strobila only measures 4-5 mm. in length. Species of
_Phylliobothrium_, _Anthobothrium_, and _Tetrarhynchus_ show a
similar but not an equal contrast between the size of the parent and
proglottis (P. J. van Beneden, "Les Vers Cestoides," _Nouv. Mém. de
l'Acad. Roy. d. Belgique_, tom. xxv. 1850).

[98] The difficult question of the nature of the Cestode body and Cestode
larvae is adequately discussed by Braun, _loc. cit._ p. 1167.

[99] Leuckart, _Die Parasiten d. Menschen_ [English trans. by W. E.
Hoyle]; Blanchard, _Traité de Zoologie médicale_, 1893.

[100] For a full account of the history of this subject see Leuckart,
_Parasiten d. Menschen_, p. 28; Braun, _loc. cit._ Bd. iv. p. 929 _et
seq._; Huxley, _Collected Essays_, vol. viii. p. 229.

[101] By Grassi this form is considered identical with _T. murina_. The
latter species is known, from this author's researches, to develop in
rats without migration into an intermediate host. Should Grassi's
synonymy prove correct, the presence of large numbers of this
tape-worm in man would readily receive its explanation.

[102] Leuckart, _loc. cit._ p. 752 _et seq._

[103] The distinctive features of these and the foregoing tape-worms are
given on pp. 89-90

[104] For description of the _Cercocystis_-larva see Villot, _Ann. Sci.
Nat. (Zool.)_ (6), xv. 1883, Art 4; and compare Leuckart's criticism
of this paper, "_Parasiten_," p. 979.

[105] Moniez, "Sur les Cysticerques," Paris, 1880; _Id._ "Sur les
Cestodes," 1881; Zschokke, "Recherches sur la structure anatomique et
histologique d. Cestodes," Genève, 1888.

[106] Schmidt, _Archiv f. Naturgeschichte_, Jahrg. lx. Bd. 1, 1894, p. 65.

[107] For example, the genitalia in _Dipylidium caninum_ are duplicated in
each proglottis. Other differences are noted in the following table
(pp. 89-90).

[108] See Stiles, _Centralbl. f. Bakt. u. Parasitenkunde_, 1893, xiii. p.
457 (conf. note, p. 90).

[109] Taken from Neumann, _Parasites of Domesticated Animals_, 1892, p.
448.

[110] µ = 1/1000 millimetre.

[111] For a description of these glands, and for further diagnostic details
and literature, see Stiles and Hassall, _U. S. Department of
Agriculture, Bureau of Animal Industry_, Bulletin 4, 1893.

[112] Ed. van Beneden, _Bull. Acad. Roy. Belgique_, 1876, p. 35.

[113] Whitman, _Mittheil. Zool. Stat. Neapel_, Bd. iv.; see also Braun, in
Bronn's _Thierreich_, Bd. iv. p. 253.

[114] Braun, _loc. cit._ p. 281 (with literature).

[115] Giard, "La Castration parasitaire," _Bull. Sci. d. France et de
Belgique_, 3 sér. i. 1888, p. 12.

[116] Schulze, _Abh. Akad. Berlin_, 1891, p. 1.

[117] _Arch. Naturg._ lviii. 1891, p. 66.

[118] _P. Boston Soc._ vol. vi. 1848.

[119] _Zeitschr. wiss. Zool._ Bd. v. 1854, p. 344.

[120] _Arch. Anat._ 1858, p. 289.

[121] _Ibid._ 1858, p. 558.

[122] _Mem. Ac. St. Petersb._ ser. vii. tom. xiv. 1869.

[123] _Zeitschr. wiss. Zool._ Bd. xliii. 1886, p. 481.

[124] R. von Willemoes-Suhm, _Ann. Nat. Hist._ ser. iv. xiii. 1874, p. 409.

[125] Semper, _Zeitschr. wiss. Zool._ Bd. xiii. 1863, p. 558.

[126] L. von Graff, _Morphol. Jahrb._ Bd. v. 1879, p. 430.

[127] W. A. Silliman, _Zeitschr. wiss. Zool._ Bd. xli. 1885, p. 48.

[128] du Plessis, _Zool. Anz._ vol. xv. 1892, p. 64.

[129] J. von Kennel, _Arb. Inst. Würzburg_, Bd. iv. 1877-78, p. 305.

[130] H. N. Moseley, _Ann. Nat. Hist._ ser. iv. vol. xv. 1875, p. 165.

[131] See Hubrecht, in _Verh. Ak. Amsterdam_, vol. xx. 1880; and in _Quart.
J. Micr. Sci._ vol. xx. 1880, p. 431.

[132] "Nemertinen," _Fauna und Flora G. von Neapel_, 22 Monogr. 1895.

[133] _Beiträge zur Naturgeschichte der Turbellarien_, Griefswald, 1851.

[134] _Arb. Inst. Würzburg_, Bd. iii. 1876, p. 115.

[135] _Ibid._ Bd. iv. 1877, p. 305.

[136] _Zool. Anz._ vol. viii. 1885, p. 51.

[137] _Quart. J. Micr. Sci._ vol. xxv. 1885, suppl. p. 1.

[138] _Zeitschr. wiss. Zool._ Bd. xli. 1885, p. 48.

[139] _Ibid._ Bd. liii. 1892, p. 322, and _Fauna und Flora G. von Neapel_,
22 Monogr. 1895.

[140] _Ann. Sci. Nat._ (5) vol. xvii. 1873.

[141] _Zeitschr. wiss. Zool._ Bd. iv. 1853, p. 178.

[142] Our knowledge of British species is mainly due to M‘Intosh (_British
Annelids_, Ray Society, 4to, 1873) and Riches (_Journ. Mar. Biol.
Ass._ vol. iii. 1893-1895, p. 1).

[143] _Fauna und Flora G. von Neapel_, 22 Monogr. 1895.

[144] See M‘Intosh, _British Annelids_, Ray Society, 4to, 1873.

[145] _Loc. cit._

[146] References to these works are given on p. 101.

[147] _Zitschr. wiss. Zool._ Bd. xli. 1885, p. 48.

[148] _Nature_, vol. xlvi. 1892, p. 611.

[149] _Zool. Anz._ vol. xv. 1892, p. 64.

[150] _Zeitschr. wiss. Zool._ Bd. lix. 1895, p. 83.

[151] _Arb. Inst. Würzburg_, Bd. iv. 1877-1878, p. 305.

[152] _Journ. Mar. Biol. Ass._ vol. iii. 1893-1895, p. 22.

[153] _Quart. J. Micr. Sci._ vol. xxiii. 1883, p. 349; _Ibid._ vol. xxvii.
1887, p. 605.

[154] Cf. Willey, _Amphioxus and the Ancestry of the Vertebrates_,
Macmillan, 1894.

[155] _Ann. Sci. nat._ 7, sér. vol. xiii. 1892, p. 321.

[156] E. Rohde, _SB. Ak. Berlin_, 1892, p. 515.

[157] R. Hesse, _Zeitschr. wiss. Zool._ Bd. liv. 1892, p. 548.

[158] E. Rohde, _Zool. Beitr._ Bd. i. 1885, p. 11.

[159] E. Rohde, _Zool. Anz._ xvii. 1894, p. 38.

[160] _Monographie der Nematoden_, 4to, Berlin, 1866.

[161] _Zeit. Physiol. Chem._ vol. xiv. 1890, p. 318.

[162] N. A. Cobb, _P. Linn. Soc. N.S. Wales_, 2nd ser. vol. vi. 1891, p.
143.

[163] _Monographie der Nematoden_, Berlin, 1866, p. 192.

[164] _Zool. Anz._ vol. xvi. 1893, p. 432.

[165] _Arch. Naturg._ 60 Jahrg. Bd. i. 1894, p. 255.

[166] _SB. Ak. Berlin_, 1891, p. 57.

[167] [Hamann subsequently withdrew these statements.]

[168] Leuckart, _The Parasites of Man_, English Trans. by W. E. Hoyle,
Edinburgh, 1886, p. 56.

[169] O. Bütschli, _Zeitschr. wiss. Zool._ Bd. xxvi. 1876, p. 103.

[170] O. Hamann, _Centrlb. Bakter._ vol. xi. 1892, p. 501.

[171] _Zeitschr. wiss. Zool._ vol. xxiii. 1873, p. 402.

[172] _Ibid._ vol. xlii. 1885, p. 708.

[173] _Ann. Nat. Hist._ 5th ser. vol. ix. 1882, p. 301.

[174] _Macleay Memorial Volume_, Sydney, 1893, p. 252; and _Proc. Linn.
Soc. N.S.W._ 2nd ser. vol. v. 1890, p. 449.

[175] 4th edition, 1880.

[176] _Compendium der Helminthologie_, Hannover, 1878, and _Nachtrag_,
1889.

[177] A. Heller, "Darmschmarotzen" in v. Liemssen's _Handb. d. sp. Path. u.
Ther._ vol. vii.

[178] Cobbold's _Parasites_, London, 1879, p. 246.

[179] _Arch. Zool. exper._ 1 sér. tom. vii. 1878, p. 283.

[180] _Arch. Zool. exper._ 1 sér. tom. vii. 1878, p. 283.

[181] Balbiani, _Anat. Physiol._ 7th year, 1870-71, p. 180.

[182] _A Treatise on Parasites and Parasitic Diseases._ English Trans. by
G. Fleming, London, 1892.

[183] _Journ. Roy. Agric. Soc._ 3rd series, vol. iv. 1893.

[184] _Sci. Mem. Medic. Officers, Army of India_, vol. vii. 1892, p. 51.

[185] Shipley, _Proc. Phil. Soc. Camb._ vol. viii. 1892-95, p. 211.

[186] "The Distribution, etc., of _Filaria sanguinis hominis_," _Trans. of
7th Inter. Congress of Hygiene_, vol. i. 1892, p. 79.

[187] v. Linstow, _Arch. mikr. Anat._ vol. xl. 1892, p. 498.

[188] zur Strassen, _Zeitschr. wiss. Zool._ vol. liv. 1892, p. 655.

[189] Rud. Leuckart, _Abh. Sachs. Ges._ vol. xiii. 1887, p. 567.

[190] _Macleay Memorial Vol._ Sydney, 1893, p. 253.

[191] _Centrbl. Bakter._ vol. viii. 1890, p. 489.

[192] J. Percival, _Nat. Sci._ vol. vi. 1895, p. 187.

[193] A. Strubell, _Bibl. Zool._ Bd. i. Heft 2, 1888, p. 1.

[194] _C. R. Ac. Sci._ cxviii. 1894, p. 549.

[195] _Bihang Svenska Ak. Handl._ viii. No. 11, 1883.

[196] _Anat. Untersuch. ü. freilebende Nordsee-Nematoden_, Leipzig, 1886.

[197] Cobb, _P. Linn. Soc. N. S. Wales_, 2nd ser. viii. 1893, p. 389.

[198] _Zeitschr. wiss. Zool._ Bd. xvii. 1867, p. 539.

[199] Panceri, _Atti Acc. Napoli_, vii. 1878, No. 10.

[200] Panceri, _Atti Acc. Napoli_, vii. 1878, No. 10.

[201] _Arch. Naturg._ 35 (i.), 1869, p. 112.

[202] _Zeitschr. wiss. Zool._ Bd. xlii. 1885, p. 708.

[203] _Arch. Naturg. Jahrg._ iii. Bd. i. 1837, p. 52; and van Beneden,
_Animal Parasites_, p. 91. International Sci. Series.

[204] F. Vejdovsky, _Zeitschr. wiss. Zool._ Bd. xliii. 1886, p. 369;
_Zeitschr. wiss. Zool._ Bd. xlix. 1888, p. 188.

[205] _Arch. mikr. Anat._ Bd. xxxvii. 1891, p. 239.

[206] _Arch. mikr. Anat._ Bd. xxxiv. 1889, p. 248.

[207] A. E. Verrill, _P. U. S. Mus._ vol. ii. 1879, p. 165.

[208] O. Bürger, _Zool. Jahrb. Anat._ Bd. iv. 1891, p. 631.

[209] H. B. Ward, _Bull. Mus. Harvard_, vol. xxiii. 1892-93, p. 135.

[210] _Mem. Acc. Torino_, 2nd ser. vol. xl. 1890, p. 1.

[211] _Centrlb. Bakter._ Bd. ix. 1891, p. 760.

[212] _Zeitschr. wiss. Zool._ Bd. vii. 1856, p. 1.

[213] _Zool. Anz._ vol. x. 1887, p. 602.

[214] Von Linstow, Hannover, 1878, and Nachtrag, 1889.

[215] H. B. Ward, _P. Amer. Ac._ new ser. vol. xix. 1892, p. 260.

[216] _Jen. Zeitschr._ Bd. xxv. 1891, p. 113.

[217] _Bibl. Zool._ Bd. ii. Heft 7. 1893.

[218] _Jen. Zeitschr._ Bd. xxv. 1891, p. 113.

[219] _Zool. Anz._ Bd. xv. 1892, p. 195.

[220] _Zool. Anz._ vol. xv. 1892, p. 52.

[221] _Zool. Anz._ vol. viii. 1885, p. 19.

[222] Shipley, _Quart. J. Micr. Sci._ vol. xxxix. 1896.

[223] O. Hertwig, _Jen. Zeitschr._ Bd. xiv. 1880, p. 196.

[224] P. Gourret, _Ann. Mus. Marseille_, tom. ii. Mem. 2, 1884, p. 103.

[225] _Bibl. Zool._ vol. i. 1888-89, p. 1.

[226] Scott, _Annals of Scottish Natural History_, 1892 and 1893.

[227] E. Béraneck, _Rev. Zool. Suisse_, vol. iii. 1895, p. 137.

[228] _Ann. Mag. Nat. Hist._ 6th ser. vol. xiii. 1894, p. 440.

[229] _Archiv Naturg._ 58 Jahrg. Bd. i. 1892, p. 333.

[230] I Chetognati, _Flora u. Fauna d. Golfes von Neapel_, Mon. v. 1883.

[231] _loc. cit._

[232] _loc. cit._

[233] _The Rotifera_, two vols, and supplt. London, 1886-89.

[234] _Phil. Trans._ vol. xix. No. 220, p. 254 (abridged ed. vol. iii.
1705, p. 651).

[235] _Ibid._ vol. xxiii. No. 283, p. 1304 (abridged ed. vol. v. p. 6).

[236] _Ibid._ vol. xxiii. No. 295, p. 1784 (abridged ed. vol. v. p. 175).

[237] _Ibid._ No. 337, vol. xxviii. 1714, p. 160.

[238] _Employment for the Microscope._ London, 1785.

[239] Paris, 1841.

[240] _Quart. Journ. Micr. Sci._ vol. i. 1853, pp. 3-8, 65-76.

[241] _Trans. Micr. Soc. London_, vol. i. (n.s.), 1853, pp. 1-19.

[242] _Verh. Ges. Würzb._ vol. iv. 1854; _Zeitschr. wiss. Zool._ vols. iii.
vi. 1851-55.

[243] _Zeitschr. wiss. Zool._ vols. vii. ix. xii. 1856-58-63.

[244] London, 1861.

[245] _Zeitschr. wiss. Zool._ vol. xxxix. 1883.

[246] _Ann. Nat. Hist._ ser. 6, vol. v. 1890, p. 1; viii. 1891, p. 34.

[247] _Jen. Zeitschr. Nat._ vol. xix. 1886; and _Zeitschr. wiss. Zool._
vols. xliii. xlix. 1886-90.

[248] _Zeitschr. wiss. Zool._ vol. xliv. 1886, p. 273.

[249] _Ibid._ vol. xliv. p. 396; xlvii. 1888, p. 353; liii. 1892, p. 1.

[250] For additions see Rousselet, _J. Roy. Micr. Soc._ 1893 and 1897.

[251] See p. 228.

[252] _Quart. Journ. Micr. Soc._ (n.s.) vol. xxiv. 1884, p. 352.

[253] The definition of the Orders and systematic position of the genera
and species referred to under this head will be found in a following
section (pp. 220 f.).

[254] Reprinted in Baker's _Employment for the Microscope_, 1785, pp. 267
f.

[255] "_Wheel Animals_, though found with most Certainty in Leaden Gutters,
etc. are often discovered in the Waters of some Ditches, and likewise
in Water that has stood a considerable Time even in the House; for I
have often met with them, in sufficient Plenty, in a Sort of slimy
Matter that is apt to be produced on the Sides of Glasses and other
Vessels, that are kept long with the _Infusions of Hay_ or other
_Vegetables_; and probably they are wafted thither by the Air, when
in the Condition of little dry Globules."

[256] Gosse's account of the "Structure, Functions, and Homologies of the
Manducatory Organs in the Class Rotifera" (in _Phil. Trans._ 1856)
remains as the most complete anatomical account we have, though his
attempt to identify these parts with the modified limbs of the
Arthropod mouth has met with no support from subsequent workers.
Gosse rendered these parts clearly visible by the use of dilute
caustic alkali.

[257] A modification of this type is seen in the parasite _Drilophagus_,
where the unci and rami are two-pronged at the end, but the trophi
are not movable on one another, but protrusible as a whole to serve
as an organ of attachment to the Oligochaete _Lumbriculus_, to which
this Rotifer attaches itself. See Vejdovsky, "Ueb. _Drilophaga
bucephalus_," etc., in _SB. Böhm. Ges. Jahrg._ 1882 (1883), p. 390.

[258] "Zur Rotatorien Württemburgs," in _Jahresb. Ver. Würt._ vol. l. 1894,
p. 57.

[259] Similarly Hudson and Zelinka both regard the dorsal antenna as formed
by the coalescence of two antennae. These retain their distinctness
in _Asplanchna_; in some Bdelloida the single antenna is supplied by
a pair of nerves.

[260] _C. R. Ac. Sci._ cxi. 1890, p. 310; cxiii. 1891, p. 388.

[261] _Acta Univ. Lund._ xxviii. 1891-92.

[262] [See, however, Calman, _Natural Science_, xiii. 1898, p. 43.]

[263] _Zeitschr. wiss. Zool._ xxii. 1872, p. 455.

[264] _Arch. Zool. Exp._ sér. 2, i. 1883, p. 131.

[265] _Zeitschr. wiss. Zool._ xliv. 1886, p. 273.

[266] _Ibid._ liii. 1892, p. 1.

[267] [See further Jennings, _Bull. Mus. Harvard_, xxx. 1896, p. 1;
Erlanger and Lauterborn, _Zool. Anz._ xx. 1897, p, 452; and Lenssen,
_Zool. Anz._ xxi. 1898, p. 617.]

[268] It does not appear to us that Zelinka is justified by his account of
the development in regarding this cup as other than a part of the
disc.

[269] The classification we have adopted is a modification of that made by
Hudson and Gosse; we have divided up their first Order Rhizota into
two, and split off from Flosculariidae the family Apsilidae; removed
the Asplanchnaceae from the admittedly heterogeneous Order Ploima,
made distinct families in the Ploima for Microcodonidae and
Rhinopidae, and created a third new Order for the Seisonaceae.
Ehrenberg, Gosse, and Hudson, being the authors of most of the
genera, are designated by their initials only.

[270] This second species has also been found in the Northern United
States.

[271] This Order has been monographed recently by Janson in _Abh. Ver.
Brem._ Bd. xii. Beilage, 1893, p. 1.

[272] See Hudson in _Month. Micr. Journ._ vol. vi. 1871, pp. 121, 215, and
_Quart. Journ. Micr. Sci._ (n.s.) xii. 1872, p. 333; Lankester,
_ibid._ p. 338; Levander in _Act. Soc. Faun. Fenn._ xi. 1894.

[273] In _Denk. Ak. Wien_, vol. vii. 1854, 2 Abth., p. 15. As has been
suggested by Deby and by Daday, it is not impossible that _Hexarthra_
is identical with _Pedalion_ (and in this case the latter name, as
newer, should be suppressed in favour of the former); but we must
suppose that Schmarda's figure of the front view is a combination,
more or less from memory or notes, of two sketches or notes taken
some time before publication; the one a side view somewhat obliquely
flattened, showing the two eyes as in Levander's Fig. 3; the other a
front view, showing the two pairs of lateral limbs in their correct
positions under pressure.

[274] The male of _Rhinops vitrea_ is exceptional in possessing a complete,
functional alimentary canal, with mastax, stomach, and intestine
(Rousselet). That of _Proales werneckii_ has a mastax, but no
intestine (Rothert).

[275] For a full account of this group see Claus in _Festschr. Z.-B. Ges.
Wien_, 1876, p. 75; and Plate in _Mt. Stat. Neapel_, vol. vii.
1886-87, p. 234; _Ann. Nat. Hist._ ser. 6, vol. ii., 1888, p. 86.

[276] [Eighteen more have since been recorded.]

[277] I have recently found a large species of this genus dwelling in the
shell of the large Cladoceran Crustacean, _Eurycercus lamellatus_. It
is remarkable for its power of completely telescoping its extremities
within the middle segments, and for its immense foot-glands, both
characters being doubtless correlated with its habitat. Rousselet
identifies it with _P. petromyzon_.

[278] _Month. Micr. Journ._ vol. ix. 1873, p. 287; _Journ. Quekett Club_,
ser. 2, vol. ii. 1884-86, p. 231.

[279] See Dr. Hudson's very suggestive presidential addresses to the Royal
Microscopical Society, published in their Journal, vols. ix.-xi.
1889-91.

[280] _Euchlanis lynceus._—This is clearly not an _Euchlanis_, and of the
six names referred to—_Ploesoma_, _Gomphogaster_, _Gastropus_,
_Gastroschiza_, _Bipalpus_, and _Dictyoderma_—the first has priority,
and the other five drop by the laws of zoological nomenclature.

[281] _Journ. Quekett Club_, ser. 2, vol. v. 1892-94, p. 205.

[282] _Trans. Micr. Soc._ (n.s.) i. 1853, p. 18 (read Dec. 31, 1851): "We
may say, therefore, that the Rotifera are organized upon the plan of
an Annelid larva.... I do not hesitate to draw the conclusion ...
that _the Rotifera are the permanent forms of Echinoderm larvae_, and
hold the same relation to the Echinoderms that the Hydriform Polypi
hold to the Medusae, or that _Appendicularia_ holds to the
Ascidians."

[283] _Quart. Journ. Micr. Sci._ (n.s.) vol. xvii. 1877, p. 399.

[284] _Ibid._ (n.s.) vol. xx. 1880, p. 381.

[285] _Arb. Z. Inst. Wien_, vols. i. iii. v. 1878-84; _Lehrbuch der
Zoologie_, part iii. 1891.

[286] _Zeitschr. wiss. Zool._ vol. xliv. 1886, p. 1.

[287] _The Microscope_ (Detroit), 1887-88.

[288] _Zeitschr. wiss. Zool._ xlix. 1890, p. 209.

[289] _Ann. Sci. Nat._ ser. 3, vol. xv. 1851, p. 158.

[290] _Zeitschr. wiss. Zool._ vol. xlv. 1887, pp. 401-467, t. xx-xxii.

[291] The breadth of the latter is estimated from Reinhard's figure.

[292] The Echiuroid Gephyrea (see p. 434) are by some authorities
considered to be a division of the Chaetopoda.

[293] Another worm, _Histriobdella_ (_Histriodrilus_) _homari_, which is
parasitic on the eggs of the lobster, and which occurs on our coast,
has been placed amongst the Archiannelida. It is a minute form, with
peculiarities in its anatomy which render its affinities uncertain.

[294] _Quart. J. Micr. Sci._ xxvii. 1887, p. 109.

[295] _J. Mar. Biol. Assoc._ vol. i. (n.s.) 1889-90, p. 119.

[296] Schimkewitsch, _Zeitschr. f. wiss. Zool._ lix. 1895, p. 46.

[297] Hatschek, _Arb. Zool. Inst. Wien_, iii. 1881, p. 79.

[298] Fraipont, "Le Genre Polygordius," _Fauna u. Flora des Golfes v.
Neapel_, Monogr. xiv. 1887.

[299] T. J. Parker, _Lessons in Elementary Biology_, London, 1891, p. 267,
gives a full account of the anatomy and development of _Polygordius_.

[300] "Die Capitelliden," _Fauna u. Flora d. Golfes v. Neapel_, Monogr.
xvi. 1887, p. 350.

[301] _Encyclopaedia Britannica_, 9th ed., Art. "Mollusca," p. 652.

[302] Benham, "The Post-Larval Stage of _Arenicola_," _J. Mar. Biol.
Assoc._ iii. (n.s.) 1893, p. 48.

[303] The blood is colourless in Syllidae and Nephthydidae.

[304] Ehlers states that some Eunicidae have green blood.

[305] Benham, _Quart. J. Micr. Sci._ xxxix. 1896, p. 1.

[306] Schaeppi, _Jena. Zeit._ xxviii. 1894, p. 217.

[307] Goodrich, _Quart. J. Micr. Sci._ xxxiv. 1893, p. 387.

[308] Benham, _Quart. J. Micr. Sci._ xxxii. 1891, p. 325. See also Bourne
(nephridium of _Polynoë_), _Tr. Linn. Soc._ (_Zool._), ii. 1883, p.
357; Meyer, for nephridium of Terebellidae, Sabellidae, and
Cirratulidae, in _Mt. Zool. Stat. Neapel_, vii. 1887, p. 592.

[309] It is worthy of note that in _Aeolosoma_ alone amongst the
Oligochaeta does the brain lie in the prostomium in the adult.

[310] Andrews, "The Eyes of Polychaetes," _J. Morph._ vii. 1892, p. 169.

[311] Wistinghausen, "Entwick. v. _N. dumerilii_," _Mt. Zool. Stat.
Neapel_, x. 1891, p. 41.

[312] This is a modification of the classification proposed by me at the
meeting of the British Association at Oxford, 1894 (see Report, p.
696). For further characteristics of these Orders and sub-Orders see
below Chap. XII. Ehlers, "Die Borstenwürmer," 1864, gives a
historical survey of the group, and enumerates the earlier
classifications.

[313] In _Coabangia_ (see p. 284) the anus is near the anterior end, on the
ventral surface.

[314] It is doubtful whether these organs are palps or only lateral lips.

[315] Pruvot traced the nerve supply to these organs, and thus established
their homology. _Arch. d. Zool. Expér._ (ser. 2) iii. 1885, p. 211.

[316] Meyer, "Stud. ub. d. Körperbau der Anneliden," _Mt. Zool. Stat.
Neapel_, vii. 1887, p. 592; viii. 1888, p. 462. In this work a great
number of important and interesting anatomical facts are recorded
with respect to the Terebelliformia and Sabelliformia, as well as
certain details as to the structure and development of the nephridia.

[317] In some of the members of this family paired lateral tentacles appear
to exist.

[318] It is possible that some of these may be peristomial.

[319] Individual cases in which chaetae are present have been recorded.

[320] Meyer, _loc. cit._

[321] Haswell, _P. Linn. Soc. N.S. Wales_, vii. 1883, p. 251.

[322] Eisig, "Die Capitelliden," _Fauna u. Flora G. v. Neapel, Monogr._
xvi. 1887, p. 331.

[323] Compare with this the muscular organ of _Dinophilus_, p. 243,
_Protodrilus_, and a similar structure which occurs in Terebellids.

[324] Korschelt, "Über Ophryotrocha puerilis," _Zeitschr. f. wiss. Zool._
lv. 1893, p. 224.

[325] Eisig, _Mt. Zool. Stat. Neapel_, ii. 1881, p. 255.

[326] They are specially large also in the Typhloscolecidae; while
Racovitza (_Ann. Mag. N. H._ (ser. 6), xv. 1895, p. 279) has recently
suggested that the caruncle of Amphinomidae belongs to the category
of nuchal organs, and compares it with the ciliated lappets of
_Pterosyllis_.

[327] Ehlers, _Zeitschr. f. wiss. Zool._ liii. 1892, p. 217.

[328] See Claparède and Metschnikoff, "Beit. zur Kennt. d. Entwick der
Chaetopoden," _Zeitschr. f. wiss. Zool._ xix. 1869, p. 163; and
Fewkes, "On the Development of certain Worm Larvae," _Bulletin Mus.
Harvard_, xi. 1883, p. 167.

[329] For an account of the anatomy and development of a Trochosphere, see
Hatschek, on _Eupomatus_, in _Arbeit. Zool. Inst. Wien_, vi. 1885.
Also Meyer, _Mt. Zool. Stat. Neapel_, viii. 1888, p. 462; and for
Polynoid larva see Häcker, _Zool. Jahrb. Abth. Anat._ viii. 1895, p.
245.

[330] See Meyer (ref. on p. 261).

[331] Many of the Polynoids are sexually dimorphic.

[332] Claparède, "Annélides Chétopodes du Golfe de Naples," Supplement,
1870; and Wistinghausen, _Mt. Zool. Stat. Neapel_, x. 1891, p. 41.

[333] Claparède used the term "epigamous" for this phase; Ehlers employed
the term "epitokous," whilst he called the "Nereid" phase "atokous,"
under the impression that the worm did not become mature in this
condition.

[334] Malaquin gives a detailed account of the asexual reproduction in
Syllidae in _Recherches sur les Syllidiens_, Lille, 1893, and in
_Revue Biol. d. Nord de la France_, iii. 1891. See also St. Joseph,
"Les annelides polychétes des côtes de Dinard," _Ann. Sci. Nat.
Zool._ (7th ser.) i. 1886, p. 134.

[335] Alex. Agassiz, _Boston J. Nat. Hist._ vii. 1863, p. 384.

[336] Huxley, _Edinb. New Philosoph. Journ._ 1855, i. p. 113.

[337] "Challenger" Reports, vol. xii. 1885, "Polychaeta," p. 198; and Oka,
_Zoolog. Centralbl._ ii. 1895, p. 591.

[338] Two new heads have been observed in _Typosyllis variegata_ by
Langerhans, and two new tails in another _Syllis_.

[339] Dalyell, _The Powers of the Creator revealed, etc._, vol. ii. 1853,
p. 225 _et seq._

[340] von Kennel, _Arb. Zool. Instit. Würzburg_, vi. 1883, p. 259.

[341] Leidy, _Proc. Acad. Nat. Hist. Philadelphia_, 1883, p. 204.

[342] Giard, _C. R. Soc. Biol._ v. 1893, p. 473.

[343] See M‘Intosh, _Ann. Mag. Nat. Hist._ (ser. 4) ii. 1868, p. 276.

[344] Lankester has suggested that a strong acid is secreted for the
purpose, see _Ann. Mag. Nat. Hist._ (ser. 4) i. 1868, p. 233.

[345] M‘Intosh, _Ann. Mag. Nat. Hist._ (ser. 6) xiii. 1894, p. 1.

[346] Dalyell, _The Powers of the Creator revealed_, ii. 1853, p. 217.

[347] Watson, _Journ. R. Mic. Soc._ 1890, p. 685; see also Dalyell, _loc.
cit._ ii. p. 195.

[348] Schmiedeberg, _Mt. Zool. Stat. Neapel_, iii. 1882, p. 373.

[349] For pelagic forms, see Camille Viguier, _Arch. de Zool. Expér._ (ser.
2) iv. 1886, p. 347; also Reibisch, _Die pelag. Phyllodociden u.
Typhloscoleciden d. Plankton Exped._ 1895.

[350] Lankester, _Journ. Anat. and Physiol._ 1868, p. 114; and 1870, p.
119; see also MacMunn, "On the Chromatology of the Blood in some
Invertebrates," _Quart. J. Micr. Sci._ xxv. 1885, p. 469.

[351] For coloured pictures of worms consult Schmarda, "Neue wirbellose
Thiere," 2nd part, 1861; Milne Edwards in Cuvier's "Règne Animal"
(Ed. Disciples de Cuvier).

[352] Semper, _Animal Life_, "Internat. Sci. Series," 1881, p. 401.

[353] The experiments were made by Mr. Garstang at the Laboratory of the
Marine Biological Association, and are recorded by Poulton in _The
Colours of Animals_, "Internat. Sci. Series," 1890, p. 201.

[354] Panceri, _Atti Acad. Sci. Napoli_, vii. 1875.

[355] M‘Intosh, H.M.S. "Challenger" Reports, "Polychaeta," vol. xii. p. ix.

[356] For an account of these worms see M‘Intosh, _loc. cit._ p. 257.

[357] For a list of parasitic Polychaetes see St. Joseph, _Ann. Sci. Nat._
(ser. 7) v. 1888, p. 141.

[358] Semper, _loc. cit._ p. 340.

[359] See "Challenger Reports," and St. Joseph, _loc. cit._

[360] "Challenger" Reports, _loc. cit._ p. xxx.

[361] See Hornell, _Fauna of Liverpool Bay_, Report III. 1892, p. 126.

[362] Zittel, _Handbuch d. Palaeontologic_ (_Palaeozoologie_), i. 1876-80,
p. 562.

[363] Ehlers, _Zeitschr. f. wiss. Zool._ xviii. 1868, p. 241.

[364] The Chaetopteridae may have to be placed elsewhere in the system, as
they are peculiarly modified, and present features recalling the
Cryptocephala, from which it is possible they have descended.

[365] Meyer (_Mt. Zool. Stat. Neapel_, vii. 1887, p. 669, note) suggests
that the tentacular filaments of Cirratulids are really prostomial,
but have shifted back on to the peristomium, or even farther.

[366] It is probable that the genital ducts of _Sternaspis_ and
Chlorhaemids are modified nephridia.

[367] The character of head and parapodium in each family will be gathered
from the figures accompanying the general description in Chap. X., so
that _detailed_ description is unnecessary. In all cases the chaetae
form valuable specific characters.

The examples of the various families are British, unless the opposite
is expressly stated; but most of them are not confined to our shores,
and the foreign localities are usually given. No attempt is made to
enumerate all the British species.

The following books may be found useful for identifying the worms:—

Claparède, _Recherches anat. sur les Annélides observées dans les
Hebrides_, 1861; _Annélides Chétopodes du golfe de Naples_, 1868,
and Suppl., 1870.

Cunningham and Ramage, "Polychaeta Sedentaria of the Firth of
Forth," _Trans. Roy. Soc. Edinburgh_, xxxiii. 1888, p. 635.
80Ehlers, _Die Borstenwürmer_, 1868.

Johnston, "British Museum Catalogue of Non-Parasitical Worms,"
1865.

M‘Intosh, "British Annelida," _Trans. Zool. Soc._ ix. 1877, p. 371;
"Invert. Marine Fauna of St. Andrews; Annelida," _Ann. Mag. Nat.
Hist._ (4) xiv. 1874, p. 144.

Malmgren, "Nordiska Hafs-Annulater," _Öfversigt af K. Vet.-Akad.
Förhandlingar_, 1865, pp. 51, 181, 355; and "Annulata Polychaeta,"
_ibid._ 1867, p. 127.

St. Joseph, "Les Annélides Polychétes des côtes de Dinard," _Ann.
Sci. Nat._ (_Zool._) (7) vol. i. 1886, p. 127; v. 1888, p. 141;
xvii. 1894, p. 1; xx. 1895, p. 185.

[368] Malaquin, _Recherches sur les Syllidiens_, 1893; for structure of the
gizzard, see also Haswell, _Quart. J. Micr. Sci._ xxvi. 1886, p. 471;
and xxx. 1889, p. 31.

[369] See M‘Intosh's Memoirs, _loc. cit._

[370] Herein are included the various genera formed by Kinberg, Malmgren,
and others.

[371] It appears to be the same as _P. grubiana_ Clap.

[372] Marenzeller has shown that Johnston's _P. scolopendrina_ is not
identical with that of Savigny, and suggests the above name for it.

[373] F. Buchanan, "Report on Polychaetes, Part I." _Sci. Proc. Roy. Dublin
Soc._ vii. (n.s.) 1893, p. 169.

[374] _Polyodontes_ Ran. deserves mention as being a large, rare form with
peculiar pedal gland; cf. Eisig (ref. on p. 268), p. 324; and
Buchanan, _Quart. J. Micr. Sc._ xxxv. 1894, p. 433.

[375] Many authorities regard this species as synonymous with Savigny's _P.
laminosa_.

[376] According to a verbal communication from Mr. J. Hornell of Jersey,
they belong to _P. maculata_ Müll., while Mr. Garstang believes them
to belong to _Eulalia viridis_.

[377] These segmentally-arranged brown spots may perhaps be photogenic.

[378] Greef, _Acta Ac. German._, xxxix. 1877.

[379] Greef, _Zeitschr. f. wiss. Zool._ xlii. 1885, p. 432.

[380] Buchanan, _Quart. J. Micr. Sci._ xxxv. 1894, p. 445.

[381] Buchanan, _Sci. Proc. R. Dublin Soc._ viii. (n.s.) 1893, p. 169.

[382] Reibisch, _Phyllodociden u. Typhloscoleciden d. Plankton Exped._
1895.

[383] The British species is usually referred to as _C. insignis_ Baird,
but Joyeux Laffuie (_Arch. Zool. Exp._ (ser. 2) viii. 1890, p. 244)
has shown that there is only one European species. It is possible
that there is a closer affinity with the Sabelliformia than is at
present supposed.

[384] Compare _Sternaspis_, p. 336.

[385] For literature, see Benham, _Quart. J. Micr. Sci._ xxxix. part 1,
1896, p. 1.

[386] F. Buchanan, _Quart. J. Micr. Sci._ xxxi. 1890, p. 175.

[387] In some genera there are no gills, _e.g._ _Leaena_.

[388] These characters are not necessarily generic.

[389] Eisig, "Die Capitelliden," _Fauna u. Flora G. v. Neapel_, Monogr.
xvi. 1887.

[390] Ed. Meyer., _Arch. mikr. Anat._ xxi. 1882, p. 769.

[391] Vejdovsky, _Denk. Akad. Wien_, xliii. 1882, part 2, p. 33; and
Rietsch, _Ann. Sci. Nat._ (_Zool._) ser. 6, xiii. 1882, art. 5.

[392] For anatomy see Meyer, _Mt. Zool. Stat. Neapel_, vii. 1887.

[393] Andrews, _Journ. Morph._ v. 1891, p. 271.

[394] A. G. Bourne, _Quart. J. Micr. Sci._ xxiii. 1883, p. 168.

[395] Closely allied is _Manayunkia_ Leidy, which occurs in fresh-water
lakes of America. Another fresh-water genus is _Coabangia_ Giard,
which perhaps deserves the creation of a special family. The anus is
ventral and anterior. The chaetae are peculiarly arranged, dorsal
uncini being present only on four segments. The first body segment
carries a ventral bundle of five great "palmate" chaetae.

[396] For the anatomy see Meyer, _Mt. Stat. Neapel_, vii. 1887; see also
above, p. 306.

[397] von Graff, "Myzostomida," "Challenger" Reports, part 27, vol. x.
1884; and "Supplement," part 61, vol. xx. 1887.

[398] Marenzeller, _Anz. Akad. Wien_, xxxii. p. 192.

[399] _Mt. Zool. Stat. Neapel_, xii. 1896, p. 227; where, too, see
literature.

[400] Beard, _Mt. Zool. St. Neap._ v. 1884, p. 544.

[401] _Quart. J. Micr. Sci._ (n.s.) vol. iv. 1864, p. 258; and v. pp. 7,
99.

[402] _Zeitschr. wiss. Zool._ xix. 1869, p. 563.

[403] _De Lumbrici terrestris Historia naturali_, Brussels, 1829.

[404] _Naturg. ein. Wurm-Arten d. süssen u. salzigen Wasser_, Copenhagen,
1771.

[405] _Trans. Roy. Soc. Victoria_, vol. i. 1888, p. 1.

[406] _Phil. Trans._ clxxxvi. 1895, A, p. 383.

[407] _Mém. cour. Ac. Belg._ lii. 1890-93.

[408] _Quart. J. Micr. Sci._ xxxi. 1890, p. 83.

[409] Beddard, _Ibid._ xxxiii. 1892, p. 325.

[410] Beddard, _Ann. Mag. Nat. Hist._ (6) xiii. 1894, p. 205.

[411] _Mém. Soc. Zool. France_, iii. 1890, p. 223.

[412] _Vegetable Mould and Earthworms_, London, 1881.

[413] _Zool. Anz._ xi. 1888, p. 72.

[414] See Fletcher, _P. Linn. Soc. N.S.W._ (2) iii. 1889, p. 1542.

[415] In _Sitzungs-Ber. Böhm. Ges._ 1889, p. 183.

[416] See Dr. Rosa in _Ann. Hofmus. Wien_, vi. 1891, p. 379.

[417] _Entwickelungsgeschichtliche Untersuchungen_, Prag, Heft i. 1888, p.
33.

[418] See Kleinenberg, _Quart. J. Micr. Sci._ xix., 1879, p. 206.

[419] Both Col. Feilden and Mr. Trevor-Battye found specimens in Kolguiev.

[420] _Neue wirbellose Thiere_, Leipzig, ii. 1861, p. 11.

[421] _Kew Bull. Misc. Information_, No. 46, 1890.

[422] _Rev. Biol. Nord France_, i. 1889, p. 197.

[423] _SB. Ges. naturf. Berlin_, 1893, p. 19.

[424] _System u. Morph. d. Oligochaeten_, Prag, 1884.

[425] See my text-book of Zoogeography (Cambridge, 1895) for fuller
treatment.

[426] _Ann. Mag. Nat. Hist._ (6) ix. 1892, p. 12.

[427] Darwin, _Vegetable Mould and Earthworms_, p. 121.

[428] "An Attempt to classify Earthworms," _Quart. J. Micr. Sci._ xxxi.
1890, p. 201.

[429] Oxford, 1895.

[430] See especially Vejdovsky, _Syst. u. Morph. Olig._ Prag, 1884.

[431] Vejdovsky, _Monographie der Enchytraeiden_, Prag, 1879. Michaelsen,
"Synopsis der Enchytraiden," _Abh. Ver. Hamburg_, xi. 1889, p. 1.

[432] J. P. Moore, "The Anatomy of _Bdellodrilus_," _J. Morphol._ x. 1895,
p. 497.

[433] Beddard, _Trans. Roy. Soc. Edin._ xxxv. 1890, p. 629, and xxxvi.
1892, p. 1.

[434] A. G. Bourne, "On the Naidiform Oligochaeta," _Quart. J. Micr. Sci._
xxxii. 1891, p. 335.

[435] F. E. Beddard, _Trans. Roy. Soc. Edin._ xxxvi. 1892, p. 273.

[436] Vejdovsky, _System u. Morph. d. Oligochaeten_, Prag, 1884.

[437] "Anatomical Notes on _Sutroa_," _Zoe._ ii. 1892, p. 321.

[438] "Pacific Coast Oligochaeta," _Mem. California Acad. Sci._ vol. ii.

[439] _Quart. J. Micr. Sci._ xxxvi. 1894, p. 307.

[440] See Spencer, _Proc. Roy. Soc. Vict._ v. 1893, and Fletcher, _P. Linn.
Soc. N.S.W._ 1886-1888, for Australian forms; Rosa, _Ann. Mus. civ.
Genova_, vi. 1886, x. 1890, and xii. 1892, for Oriental species, etc.

[441] See Fletcher and Spencer, already quoted, for Australian species.

[442] Eisen, "Anat. Studies on _Ocnerodrilus_," _Proc. Calif. Acad._ (2)
iii. 1892, p. 228.

[443] Beddard, _Ann. Mag. Nat. Hist._ (6) x. 1892, p. 74.

[444] Beddard, _P. Z. S._ 1885 and 1895, for Antarctic Acanthodrilids;
Michaelsen, in _Jahrb. Hamburg. Anst._ 1888-95, for _Benhamia_.

[445] For a general account of the Eudrilidae, see my Monograph of the
Order Oligochaeta, Oxford, 1895.

[446] _Nouv. Arch. Mus. Paris_, viii. 1872, p. 5.

[447] The scattered literature of this family is due to Benham, Michaelsen,
Perrier, Rosa, and others.

[448] Rosa, "Revisione dei Lumbricidae," _Mem. Acc. Torino_ (2), xliii.
1893, p. 399; also the Rev. H. Friend's numerous and useful papers,
and especially "A New Species of Earthworms," _Proc. Roy. Irish Ac._
(3) ii. 1891-93, p. 402; and "The Earthworms of Ireland," _Irish
Nat._ v. 1896, p. 69, etc.

[449] In the tables the figures refer to the segments of the body. Opposite
the name of each species are two sets of lines; the upper series
indicate the segments occupied by the clitellum; the lower series
those occupied by the tubercula pubertatis. The dots indicate the
occasional extension of the clitellum or of the tubercula.

[450] "Annelés," vol. iii. 1889-90, p. 477, in the _Suites à Buffon_.

[451] See v. Kennel, _Zool. Jahrb._ ii. 1887, p. 37.

[452] _Nouvelle Monographie des Sangsues médicinales._ Paris, 1857.

[453] _Quart. J. Micr. Sci._ xxvi. 1886, p. 317.

[454] See Grube, "Annulaten" of Middendorff's _Sibirische Reise, Zoology_,
1851, p. 20; and Kowalevsky, _Bull. Ac. St. Petersb._ v. June 1896.

[455] See ref. on p. 395.

[456] Asajiro Oka, _Zeitschr. wiss. Zool._ lviii. 1894, p. 79.

[457] See Bürger, quoted on p. 403.

[458] _Loc. cit._

[459] _Quart. J. Micr. Sci._ xxiv. 1884, p. 419; see also _ibid._ xxxiv.
1893, p. 545, which is mainly a criticism of Bolsius' additions to
the very considerable literature upon the Leech nephridium.

[460] "Spermatophores as a Means of Hypodermic Impregnation," _J. Morphol._
iv. 1891, p. 361.

[461] _Zeitschr. wiss. Zool._ lviii. 1894, p. 440; and _Zool. Jahrb. Anat._
iv. 1891, p. 697.

[462] "Annelés," vol. iii. 1889-90, p. 493, in the _Suites à Buffon_.

[463] Whitman quotes with regretful approval (_Proc. Americ. Acad._ xx.
1884-85, p. 76) Sir J. Dalyell's remark, "It does not appear that the
history of the leech has advanced in proportion to the number of
_literati_ who have rendered it the subject of discussion," and adds
on his own account the following severe indictment of his
predecessors: "As a considerable share of the work done in this
direction is purely systematic, it is somewhat surprising that not a
single description of any Hirudo has been given with sufficient
accuracy and completeness for a close comparison of even its more
important external characters with those of other species."

[464] "Hirudinées de l'Italie," etc., _Boll. Mus. Zool. Torino_, vol. ix.
1894, No. 192. See also Apathy, "Süsswasser-Hirudineen," _Zool.
Jahrb. Syst._ iii. 1888, p. 725.

[465] _Zeitschr. f. die gesammt. Naturwiss._ vi. 1872, p. 422.

[466] But Pennant in his _British Zoology_ has referred to a leech which is
even larger. Upon the huge Basking shark (_Selache_) the fishermen
sometimes observe a leech, which invariably drops off when the fish
is brought to the surface, "of a reddish colour and about 2 feet in
length"; this may be a _Pontobdella_.

[467] _Ann. Mag. Nat. Hist._ (6) xii. 1893, p. 75.

[468] _Memorie sulla Storia e Notomia degli Animali senza Vertebre_, 1823.

[469] _Histoire Naturelle des Animaux sans Vertèbres_, vol. iii. 1816, p.
76.

[470] _Le Règne Animal_, 2nd ed. 1830.

[471] γέφῦρα = a bridge, _Ann. Sci. Nat._ (3), vol. vii. 1847, p. 340.

[472] Fischer, _Abh. Ver. Hamburg_, Bd. xiii. 1895, p. 1.

[473] Cuénot, _Arch. Zool. exp._ (2) ix. 1891, p. 593.

[474] _Bull. Mus. Harvard_, vol. xxi. 1891, p. 143.

[475] Shipley, _Quart. J. Micr. Sci._ vol. xxxi. 1890, p. 1.

[476] _Stud. Johns Hopkins Univ._ vol. iv. 1887-90, p. 389.

[477] Conn, _Stud. Johns Hopkins Univ._ vol. iii. 1884-87, p. 351.

[478] _Arb. Instit. Wien_, Bd. v. 1884, p. 61.

[479] Shipley, _Quart. J. Micr. Sci._ vol. xxxii. 1891, p. 111.

[480] _Proc. Roy. Soc. Edin._ xviii. 1892, p. 17.

[481] Selenka, _Die Sipunculiden_. Semper's _Reisen im Archipel d.
Philippinen_, vol. iv. 1883.

[482] _Stud. Johns Hopkins Univ._ vol. iv. 1887-90, p. 389.

[483] Selenka, _Challenger Reports_, vol. xiii. 1885.

[484] _Ann. Sci. nat._ (7) vol. xx. 1895, p. 1.

[485] _Zool. Anz._ ix. 1886, p. 574.

[486] This is not true of all species.

[487] _Acta Ac. German, Halle_, xli. Part II. No. 1, 1879.

[488] _Recueil Zool. Suisse_, iii. 1886, p. 313.

[489] _Vide_ p. 335.

[490] _P. Phys. Soc. Edinb._ vol. i. 1856, p. 165; and _Edinb. New Phil.
Journ._ vol. iv. (n.s.) 1856, p. 313; _Ann. Sci. Nat._ 4th ser. vol.
xi. 1859, p. 150; and F. D. Dyster, _Tr. Linn. Soc. London_, vol.
xxii. 1859, p. 251.

[491] _Ann. Sci. Nat._ 4th ser. vol. x. 1858, p. 11.

[492] "Beiträge zur Anatomie der Phoronis," _Inaug. Dissert. Prag._ 1889,
and _Zeitschr. wiss. Zool._ vol. li. 1891, p. 480.

[493] _P. Linn. Soc. N. S. Wales_, 1st ser. vol. vii. 1883, p. 606; and 2nd
ser. vol. vii. 1893, p. 340.

[494] _Quart. J. Micr. Sci._ vol. xxx. 1890, p. 125.

[495] _Challenger Reports_, vol. xxvii. 1888; and _Proc. Roy. Soc. Edinb._
vol. xi. 1882, p. 211.

[496] _Proc. Roy. Soc. London_, vol. xxxiv. 1883, p. 371.

[497] _Zapiski Acad. St. Petersb._ vol. xi. No. 1, 1867 (Russian). Abstract
in _Arch. Naturg._ Jahrg. xxxiii. 1867, Bd. ii. p. 235.