FOOTNOTES:
[1] See especially Moseley, Nature, 1885, p. 417.
[2] Quart. Journ. Conch. i. p. 371.
[3] Manuel de Conchyliologie et de Paléontologie Conchyliologique. Dr. P. Fischer. Paris, 1887.
[4] κεφαλή, head; γαστήρ, stomach; σκάπτειν, to dig; πέλεκυς, an axe; πούς, ποδός, a foot.
[5] Also known as Lamellibranchiata, Conchifera, and Acephala.
[6] πτερόν, wing.
[7] γλῶσσα, tongue; φέρειν, to carry.
[8] λείπειν, to be wanting.
[9] ἀμφί, on both sides; νεὕρον, nerve, vessel. Some authorities regard the Amphineura as a distinct Order.
[10] πολύς, many; πλάξ, plate.
[11] πρόσω, in front. Often alluded to in the sequel as ‘operculate Gasteropoda.’
[12] κτενίδιον, a little comb.
[13] δὐω, two; mόnos, single; ὦτα, auricles; καρδία, heart.
[14] ὄπισθεν, behind.
[15] Pulmo, a lung.
[16] στὕλος, pillar; ὄμματα, eyes.
[17] The Ascoglossa are dealt with below (chap. xv.).
[18] Beudant, by very gradually changing the water, accustomed marine species to live in fresh, and fresh-water species to live in salt water.
[19] Braun, Arch. f. Naturk. Liv. (2), x. p. 102 f.
[20] Lindström, Oef. K. Vet. Förh. Stockh., 1855, p. 49.
[21] Mendthal, Schr. Ges. Königsb., xxx. p. 27.
[22] SB. K. Akad. Wiss. Wien, 1889, p. 4, but the view is not universally accepted.
[23] Not to Nassa, as has been generally held. The shape of the operculum, and particularly the teeth of the radula, show a much closer connexion with Cominella.
[24] E.g. Bouvier, Le Natural, 1889, p. 242.
[25] Köhler, Zool. Jahrb. vii. 1893, p. 1 f; Haller, Arb. Zool. Inst. Wien, x. p. 71.
[26] Plate, SB. kön. Preuss. Ak. Wiss. Berl. 1893. p. 959.
[27] E.g. Pelseneer, Bull. Sc. France Belg. xxiv. p. 347 f.
[28] E.g. Bergh, Zool. Jahrb. v. p. 1 f.
[29] Calkins, Amer. Nat. xi. p. 687.
[30] One step even further (or perhaps it should be termed a branch derivative) is seen in the genus Smaragdia, which is probably a Neritina which has resumed a purely marine habit of life.
[31] SB. Naturf. Gesell. Leipz. 1886–87, pp. 40–48.
[32] L. and F. W. Moll. of India, iv. p. 167.
[33] T. Scott, Journ. of Conch. v. p. 230.
[34] J. S. Gibbons, ibid. ii. p. 129.
[35] Bull. Soc. Linn. Nord, Abbeville, 1840, p. 150.
[36] Joly, Comptes Rendus, 1842, p. 460; compare W. A. Gain, Science Gossip, xxvii. p. 118.
[37] Von Martens, SB. Nat. Fr. Berl. 1881, p. 34.
[38] Moquin-Tandon, Moll. de France, i. p. 116.
[39] Journ. of Conch. iii. p. 321 f.; iv. p. 13; Science Goss. 1866, p. 158.
[40] Reichel, Zool. Anz. x. p. 488.
[41] Schumann, Schr. Ges. Danz. (2) vi. p. 159.
[42] Fischer and Crosse, Mexico, p. 437.
[43] Journ. de Conch. iv. p. 397, but the species observed is not mentioned.
[44] Bull. Mus. C. Z. Harv. iv. p. 378.
[45] W. Harte, Proc. Dubl. N. H. Soc. iv. p. 182.
[46] See on the whole subject of threads G. S. Tye, Journ. of Conch. i. p. 401.
[47] Zoologist, ii. p. 296; iii. p. 833; iv. p. 1216; iii. p. 1036; iv. p. 1216; iii. p. 1037.
[48] Ann. Nat. Hist. ii. 1838, p. 310.
[49] H. W. Kew, Naturalist, 1889, p. 103.
[50] Zeit. wiss. Zool. xlii. p. 203 f.
[51] Sci. Trans. R. Dubl. Soc. (2) iv. p. 520.
[52] Zoologist, iv. p. 1504; iii. p. 1038; iii. p. 943.
[53] H. W. Kew, l. c.
[54] Zoologist, xix. p. 7819.
[55] Naturalist, 1889, p. 55.
[56] H. W. Kew, l. c.
[57] W. G. Binney, Bull. Mus. C. Z. Harv. iv. p. 144.
[58] Naturalist, l. c.
[59] Science Gossip, 1885, p. 154.
[60] R. Standen, Journ. of Conch. vii. p. 197.
[61] Journ. of Conch. v. p. 43.
[62] A. Paladilhe in MS. letter.
[63] J. S. Gibbons, Quart. Journ. Conch. ii. p. 143.
[64] Bull. Mus. C. Z. Harv. iv. p. 193.
[65] l. c. p. 362.
[66] Animal Life, p. 59.
[67] Zoologist, 1861, p. 7400; Brit. Conch. i. p. 108.
[68] H. Ullyett, Science Gossip, xxii. (1886), p. 214.
[69] Descent of Man, i. p. 325, ed. 1.
[70] Amer. Nat. xv. 1881, p. 976.
[71] W. A. Gain, quoted by H. W. Kew in Naturalist, 1890, p. 307, an article to which I am much indebted.
[72] Ann. Mag. Nat. Hist. (5) xvi. p. 519.
[73] Science Gossip, 1882, pp. 237, 262.
[74] H. W. Kew, Naturalist, 1893, p. 149, another most valuable article.
[75] Garden, v. p. 201, quoted by Kew, ut sup.
[76] Kew, ut sup.
[77] Science Gossip, 1883, p. 163.
[78] T. D. A. Cockerell, Science Gossip, 1885, p. 211.
[79] Ann. Mag. Nat. Hist. (2) vi. (1850) p. 68.
[80] Ann. Mag. Nat. Hist. (2) vi. p. 489.
[81] Ibid. (3) iii. p. 448.
[82] Amer. Nat. xi. (1877) p. 100; Proc. Calif. Ac. iii. p. 329.
[83] Gaz. Med. Alger. 1865, 5th Jan. p. 9.
[84] Science Gossip, 1867, p. 40.
[85] Ann. Mag. Nat. Hist. (2) ix. p. 498.
[86] Journ. of Conch. vi. p. 101.
[87] Naturalist, 1889, p. 55.
[88] Malak. Blätt. (2) iv. pp. 43 and 221.
[89] Phil. Trans. 1854 (1856), p. 8.
[90] Naturalist, 1891, p. 75 f.; Conchologist, ii. 1892, p. 29.
[91] Taylor, Journ. of Conch. 1888, p. 299.
[92] See Tennent’s Ceylon, i. p. 221, ed. 5.
[93] W. A. Gain, Naturalist, 1889, p. 55; Brockmeier, Nachr. Deutsch. Malak. Gesell. xx. p. 113.
[94] Ann. Mag. Nat. Hist. (2) ix. p. 498.
[95] Journ. Conch. vii. 1893, p. 158 f.
[96] I succeeded in hatching out eggs of Helix aspersa, during the very warm summer of 1893, in 17 days.
[97] Nachr. Deutsch. Malak. Gesell. xx. p. 146.
[98] Raymond, Nautilus, iv. p. 6.
[99] Quoted by Oehlert, Rév. Sc. xxxviii. p. 701.
[100] Animal Life, Intern. Scientif. Ser. ed. 1, p. 395.
[101] Zoologist, 1886, p. 491.
[102] Thomas, quoted by Jeffreys, Brit. Conch. i. p. 30.
[103] Journ. of Conch. iv. p. 117.
[104] Rev. L. Jenyns, Observations in Nat. Hist. p. 318.
[105] Id. ib. p. 319.
[106] Further detailed examples will be found in Kew, The dispersal of Shells, pp. 5–26.
[107] P. Z. S. 1888, p. 358.
[108] W. A. Gain, Naturalist, 1889, p. 58.
[109] Das Wetter, Dec. 1892. Another case is recorded in Amer. Nat. iii. p. 556.
[110] Zoologist, x. p. 3430.
[111] Science Gossip, 1888, p. 281.
[112] Lecoq, Journ. de Conch. ii. p. 146.
[113] Bouchard-Chantereaux, Ann. Sci. Nat. Zool. (4) xvi. (1861) p. 197.
[114] Forel, Ann. Sci. Nat. (3) xx. p. 576; Bretonnière, Comptes Rendus, cvii. p. 566.
[115] Brit. Mus. Collection.
[116] Thomas, quoted by Récluz in Journ. de Conch. vii. 1858, p. 178.
[117] Nat. Hist. of Ceylon, p. 382. See also T. L. Taylor, Rep. Brit. Ass. for 1848, p. 82.
[118] Dr. R. E. Grant, Edinb. Phil. Journ. xiv. p. 188.
[119] Rep. Brit. Ass. for 1848, p. 80. The statement is confirmed by Rossmässler.
[120] Journ. of Conch. iv. p. 118.
[121] Zoologist, 1887, p. 29.
[122] Arch. Zool. Exp. Gén. (2) v. p. 459 f.
[123] Journ. of Conch. iii. p. 277; compare W. M. Webb, Zoologist, 1893, p. 281.
[124] Bull. Mus. Comp. Zool. Harv. iv. p. 85.
[125] Erjavec, Nachr. Deutsch. Malak. Gesell. 1885, p. 88.
[126] Crosse, Journ. de Conch. (3) xiv. (1874) p. 223.
[127] C. Wright, Zoologist, 1869, p. 1700.
[128] W. V. Legge, Zoologist, 1866, p. 190.
[129] Blackwall, Researches, p. 139.
[130] Barrow, Travels in South Africa, ii. p. 67.
[131] Loch Creran, p. 102.
[132] Cordeaux, Zoologist, 1873, p. 3396.
[133] Amer. Nat. xii. p. 695; Science Gossip, 1865, p. 79.
[134] Journ. Trent. N. H. Soc. 1887, p. 58.
[135] Ann. Nat. Hist. iii. 1893, pp. 238, 239.
[136] Rev. Nat. Sc. Ouest, 1891, p. 261.
[137] Petit de la Saussaye, Journ. de Conch. iii. p. 97 f.
[138] J. W. Williams, Science Gossip, 1889, p. 280.
[139] Noack, Zool. JB. ii. p. 254.
[140] La Nature, xv. (2) p. 46.
[141] François, Arch. Zool. Exp. Gén. (2) ix. p. 240.
[142] A. Lang, Ber. Naturf. Ges. Freib. vi. 1892, p. 81.
[143] A. P. Thomas, Q. J. Micr. Sc. N. S. xxiii. (1883) p. 99.
[144] H. Woodward, P. Z. S. 1886, p. 176.
[145] W. E. Collinge, Zoologist, 1890, p. 467.
[146] Proc. Linn. Soc. N. S. Wales, ix. p. 944.
[147] Zoologist, xviii. (1860) p. 7136.
[148] A. Adams, Samarang, vol. ii. Zoology, p. 357.
[149] In Thomson’s British New Guinea, p. 283.
[150] Animal Life, p. 395. It should be mentioned that Von Möllendorff (Ber. Senck. Ges. 1890, p. 198) ridicules the whole theory.
[151] Von Martens, SB. Nat. Fr. Berl. 1891, p. 83.
[152] Von Martens, ibid. 1887, p. 183.
[153] SB. Nat. Gesell. Leipz. xiii.-xiv. p. 45.
[154] Garstang, Journ. Mar. Biol. Ass. N. S. i. p. 432; Giard, Bull. Sci. Fr. Belg. 1888, p. 502 f.
[155] Nautilus, vi. 1892, p. 90.
[156] R. F. Scharff, Sci. Trans. R. Dubl. Soc. (2) iv. p. 553 f.
[157] Q. Journ. Micr. Sci. N. S. xxxi. (1890) p. 41 f.
[158] A detailed account is given in Proc. Liverp. Biol. Soc. iv. (1890) pp. 150–163.
[159] Journ. Mar. Biol. Ass. N. S. i. p. 418 f.
[160] Garstang, Conchologist, ii. p. 49.
[161] Hecht, Comptes Rendus, cxv. p. 746.
[162] Conchologist, ii. p. 130.
[163] Described as a Cypraea, but no doubt an Ovula or Pedicularia: CB. Bakt. Par. v. p. 543.
[164] Von Graff, Z. wiss. Zool xxv. p. 124.
[165] Proc. Amer. Phil. Soc. xxv. p. 231.
[166] Ergeb. naturw. Forsch. Ceylon, abstr. in Journ. Roy. Micr. Soc. (2) vi. p. 412.
[167] Voyage of the Samarang, Moll. p. 69, Pl. xi. f. 1; p. 47, Pl. xvii. f. 5.
[168] E. A. Smith, Ann. Mag. Nat. Hist. (6) iii. p. 270.
[169] Journ. de Conch. (3) xxix. p. 101.
[170] Zool. Jahrb. Abth. f. Syst. v. p. 619.
[171] See especially Semper, Animal Life, Ed. 1, p. 351.
[172] Gould, Moll. of U.S. expl. exped. 1852, p. 207 (St. acicula, from Fiji).
[173] Stimpson, Proc. Bost. Soc. N. H. vi. 1858, p. 308.
[174] Pidgeon, Nature, xxxix. p. 127.
[175] W. Anderson Smith, Loch Creran, p. 46.
[176] Smart, Journal of Conch. v. p. 152.
[177] Animal Life, p. 351.
[178] Journ. of Conch. vi. 1891, p. 399.
[179] Ann. Mag. N. H. (6) vii. p. 276.
[180] Stimpson, quoted by Jeffrey’s Brit. Conch. ii. 194.
[181] Stimpson, Journ. Bost. Soc. N. H. vi. 1857, p. 48.
[182] E. H. Matthews, Conchologist, ii. p. 144.
[183] Thus Limnaea involuta, which is almost universally regarded as a good and distinct species, has been held to be no more than a variety of L. peregra produced by locality; see Zoologist, 1889, p. 154.
[184] J. W. Taylor, Journ. of Conch. v. p. 289, an interesting article, with many useful references.
[185] Möbius, Report on ‘Pommerania’ Exped. pp. 138–141.
[186] Journ. de Conchyl. xxiii. 1875, p. 105.
[187] J. W. Taylor ut sup. p. 300.
[188] Sci. Trans. R. Dubl. Soc. (2) iv. p. 555.
[189] J. S. Gibbons, Journ. of Conch. ii. p. 129.
[190] C. H. Morris, ibid. vii. p. 191.
[191] F. M. Hele, ibid. iv. p. 93.
[192] T. D. A. Cockerell, Science Gossip, 1887, p. 67.
[193] J. G. Jeffreys, British Conchology, vol. i. p. 214.
[194] Journ. of Conch. vi. p. 123.
[195] Phil. Trans. 1889, vol. 180 B, p. 207. A somewhat similar case (the celebrated Steinheim series of Planorbis) is dealt with by Hilgendorf, MB. Akad. Berl. 1866, p. 474; and Hyatt, Proc. Amer. Ass. Sc. xxix. p. 527.
[196] J. B. Bridgman, Quart. Journ. Conch. i. p. 70.
[197] W. C. Hey, Journ. of Conch. iii. p. 268.
[198] Zool. Anz. xiii. p. 662.
[199] J. Madison, Journ. of Conch. v. p. 260.
[200] Quart. Journ. Conch. i. 339.
[201] Whitfield, Bull. Amer. Mus. N. H. i. p. 29.
[202] Amer. Nat. xiv. p. 51.
[203] Animal Life, Ed. 1, p. 160 f.
[204] Conch. Syst. ii. p. 262 n.
[205] P. L. Simmonds, Commercial Products of the Sea, p. 278.
[206] Benderloch, p. 118.
[207] C. Hedley in J. P. Thomson, Brit. New Guinea, p. 283.
[208] Most of the above facts are derived from a study of a collection of native implements, weapons, ornaments, etc., in the Antiquarian Museum at Cambridge.
[209] Thurston, Notes on the Pearl and Chank Fisheries, Madras, 1890.
[210] See in particular, P. L. Simmonds, The Commercial Products of the Sea.
[211] H. Friend, Field Club, iv. 1893, p. 100.
[212] Nature, xxxi. 1885, p. 492.
[213] W. Anderson Smith, Benderloch, p. 173.
[214] Dominique, Feuill. Nat. xviii. p. 22.
[215] SB. Nat. Fr. Berl. 1889, p. 197.
[216] A. Adams, Voyage of the ‘Samarang,’ ii. p. 308.
[217] Much information has been derived, on this subject, from Bertram’s Harvest of the Sea, Simmonds’ Commercial Products of the Sea, the publications of the Fisheries Exhibition, especially vol. xi. (Anson and Willett); see also Philpots, Oysters and all about them.
[218] Juvenal, Sat. iv. 140–142.
[219] Hist. Nat. ix. 79.
[220] Vol. Max. ix. 1.
[221] Quart. Journ. Micr. Sc. xxvi. p. 71.
[222] See G. H. Lewes, Sea-side Studies, p. 339.
[223] Bull. U.S. Fish. Comm. v. p. 161.
[224] W. Anderson Smith, Loch Creran, p. 228.
[225] Longmans’ Magazine, June 1889.
[226] St. James’s Gazette, 6th January 1893.
[227] Also at Arcachon (W. A. Herdman, Nature, 1893, p. 269).
[228] See especially Hoek, Tijdschr. Ned. Dierk. Vereen, Suppl. Deel, i. 1883.
[229] Benderloch, p. 136.
[230] This is the view of E. Ray Lankester, Quart. Journ. Micr. Sc. xxvi. 80.
[231] De Quatrefages, Rambles of a Naturalist.
[232] Quoted by Jeffreys, Brit. Conch., ii. p. 109.
[233] M. S. Lovell, Edible Mollusks, p. 49.
[234] Science, vii. p. 175.
[235] Hist. Nat. ix. 82.
[236] De re rustica, iii. 14.
[237] Epistles, i. 15.
[238] Hor. Sat. II., iv. 58, tr. Conington.
[239] Roberts, Zoologist, 1885, p. 425.
[240] Hist. Nat. xxx. 15, 19.
[241] Science Gossip, 1891, p. 166.
[242] Jeffreys, Brit. Conch. iii. p. 355.
[243] W. Clark, Mag. Nat. Hist. xvi. p. 466.
[244] Examples will be found in Journ. Linn. Soc. Zool. xi. p. 90; Ann. Sc. Nat. xx. p. 472; Zeit. wiss. Zool. xxiv. p. 419.
[245] Herdman, Proc. Liverp. Biol. Soc. iii. p. 30.
[246] Garrett, Journ. Ac. Nat. Sc. Phil. viii. (1880).
[247] J. Bladon, Zoologist, xvi. p. 6272.
[248] Lo Bianco, MT. Zool. Stat. Neap. viii. p. 414.
[249] Animal Life, pp. 126, 135.
[250] R. Rimmer, Land and Fresh-Water Shells, p. 119.
[251] Journ. de Conch. ii. p. 245.
[252] Journ. de Conchyl. iii. p. 107.
[253] Jeffreys, Brit. Conch. iii. p. 359; Sauvage, Journ. de Conchyl. xxi. p. 122.
[254] Hermaphroditism seems to occur in (a) whole families, e.g. Anatinidae and the Septibranchia; (b) genera, e.g. Cyclas, Pisidium; (c) single species, e.g. in the generally dioecious genera Ostrea, Pecten, Cardium.
[255] δὐω, two; μόνος, single; γόνος, semen; πόρος, passage.
[256] Von Brunn, Arch. Mikr. Anat. xxiii. p. 413.
[257] Hist. Anim. v. 6 and 12, iv. 1, ed. Bekker, 1837.
[258] ‘On pourra constater si ce ne seraient pas des parties détachées de quelque céphalopode dans le but de servir à le fécondation,’ Hist. Nat. Helminthes, 1845, p. 482.
[259] Steenstrup, Ann. Mag. Nat. Hist. (2), xx. p. 81 f.
[260] C. Ashford, Journ. of Conch. iii. p. 239, iv. pp. 69, 108.
[261] W. E. Collinge, Zoologist, 1890, p. 276.
[262] Pelseneer, Comptes Rendus, cx. p. 1081.
[263] Kon. Vet. Akad. Handl. 1848, pp. 329–435.
[264] P. Z. S. 1891, p. 52 f.
[265] The result of some experiments by Professor Herdman upon Littorina rudis, tends to show that it can live much better in air than in water, and goes far to support the view that the species may be undergoing, as we know many species must have undergone (see p. 20), a transition from a marine to a terrestrial life. It was found that marked specimens upon the rocks did not move their position for thirty-one successive days (Proc. Liverp. Biol. Soc. iv. 1890, p. 50).
[266] Diminutive of κτείς, a comb.
[267] Stoliezka, quoted in Journ. de Conch. xviii. p. 452.
[268] ζύγος, a yoke, from the symmetrical position of the branchiae.
[269] Pelseneer, ‘Challenger’ Reports, vol. xxiii. part lxvi.
[270] Zoologist, xii. p. 4248.
[271] Mollusques de France, i. p. 81.
[272] N. Denk. Schw. Ges. xxix. (2) p. 196 f.
[273] Bergh, Morph. Jahrb. x. p. 172.
[274] P. Fischer, Journ. de Conch. ix. p. 101.
[275] Bull. Mus. C. Z. Harv. xviii. p. 434.
[276] Pelseneer, Comptes Rendus, cvi. p. 1029.
[277] E.g. Kollmann, Zeit. wiss. Zool. xxvi. p. 87.
[278] Proc. Roy. Soc. 1873, p. 70.
[279] Griesbach (Arch. mikr. Anat. xxxvii. p. 22) finds haemoglobin in several bivalves, e.g. Poromya granulata, Tellinata planata, Arca Noae, and Pectunculus glycimeris.
[280] Trans. Roy. Soc. N. S. Wales, xxii. p. 106.
[281] Pelseneer, Comptes Rendus, cx. p. 154.
[282] Science, iv. p. 50.
[283] P. Fischer, Journ. de Conchyl. (3) xxvii. p. 201.
[284] Journ. of Conch. vi. p. 349 ff.
[285] Quart. Journ. Micr. Sc. N.S. xv. p. 37.
[286] Ann. Mag. Nat. Hist. (2), xx. p. 336.
[287] V. Willem (Arch. Biol. ut infr.) denies this, and declares that Cyclostoma is only very sensitive to movements. The present writer has often approached, with the greatest care, a crawling Cyclostoma, but it always withdrew into its shell or fell to the ground when approached within about 10 or 12 inches.
[288] Arch. Biol. xii. 1892, p. 57.
[289] ‘Challenger’ Reports, Zoology, vol. xxvii. part lxxiv. p. 3.
[290] Animal Life, p. 372 f.
[291] Bergh, Morph. Jahrb. x. p. 172.
[292] Ann. Mag. Nat. Hist. (5) xiv. p. 141.
[293] The nature of the grouping of the eyes into rows varies considerably in different species. As a rule, the rows radiate from the beak, but occasionally they run parallel to the girdle. In Tonicia lineolata Fremb., they are grouped, as it were, under the shelter of strongly marked longitudinal wavy lines.
[294] Shell-Eyes in other Mollusca.—The Rev. J. E. Tenison-Woods (Trans. Linn. Soc. N. S. Wales, xxii. p. 106) is of opinion that ‘shell-eyes’ are by no means confined to the Chitonidae, but that, in fact, multiplicity of eyes of this kind is the rule rather than the exception among the Mollusca. He finds (1) exceedingly minute and numerous ‘eyes’ on the outer surface of the shell in both univalves and bivalves; (2) large and solitary ‘eyes’ in the shell substance; (3) eyes on the mantle lobes in both univalves and bivalves; (4) eyes on the opercula.
[295] Mitth. Stat. Zool. Neap. v. p. 447 ff.
[296] W. Patten, Mitth. Zool. Stat. Neap. vi. (1886) pp. 546, 605 f.
[297] Benderloch, p. 136.
[298] Quart. Journ. Micr. Soc. xx. p. 443.
[299] Quart. Journ. of Conch. i. p. 368.
[300] British Conchology, i. p. xxviii.
[301] Science Gossip, 1865, p. 259.
[302] Mollusques de France, i. p. 130.
[303] E.g. Sochaczewer, Zeits. wiss. Zool. xxxv. p. 30.
[304] Zool. Anz. 1882, p. 472.
[305] Zoologist, iv. p. 1266.
[306] Journ. Mar. Biol. Ass. N.S. i. p. 217.
[307] Moquin-Tandon, Moll. de France, i. p. 133.
[308] Zool. Jahrb. Anat. iv. (1890) p. 501.
[309] Baudon, Rév. Mag. Zool. 1852, p. 575.
[310] Arch. Zool. Exp. Gén. (2) v. 1887, p. 2; compare also C. H. Hurst, Natural Science, ii. pp. 360, 421.
[311] Compare Pelseneer, Bull. Sci. Fr. Belg. (3) xix. pp. 107, 182.
[312] Pelseneer, Arch. Biol. viii. p. 723.
[313] Also known as labial and supra-oesophageal ganglia.
[314] Wivén, however (K. Sv. Vet. Ak. Handl. xxiv. 1892, No. 12), describes transverse connectives in Chaetoderma.
[315] στρεπτός, twisted; εὐθύς, straight.
[316] With the exception of Actaeon, which is streptoneurous (Bouvier, Comptes Rendus, cxvi. p. 68).
[317] This fusion of the cerebral and pleural ganglia and the consequent union of the cerebro-pedal and pleuro-pedal commissures can be recognised by sections of the mass (Pelseneer, Comptes Rendus, cxi. p. 245).
[318] There is practically no pharynx in the Pelecypoda, the mouth opening directly into the oesophagus.
[319] Radere, to scrape; ὸδούς, tooth; φέρειν, to carry.
[320] The mechanism of the radula has been dealt with by Geddes, Trans. Zool. Soc. x. p. 485. Rücker has observed (Ber. Oberhess. Gesell. Nat. Heilk. xxii. p. 207) that the radula in Helix pomatia is the product of five rows of cells; the use of the first row is uncertain, the second forms the membrane of the radula, while rows three to five originate the teeth.
[321] Jahrb. Deut. Malak. Gesell. iii. p. 193.
[322] The whole of the radulae and jaws figured in this work are taken from the original specimens in the collection of the Rev. Prof. H. M. Gwatkin, who has always been ready to give me the run of his cabinets, which probably contain the finest series of radulae in the world. To his kindness I owe the following description of the process of mounting: “The first step is to obtain the radula. Dissection is easy in species of a reasonable size. On opening the head from above, so as to lay open the floor of the mouth, the radula itself is seen in most of the marine species, though in others it is contained in a sort of proboscis; and in the Pulmonata and others the student will find the buccal mass, with commonly a brown mandible at its front end, and the lingual ribbon in its hinder part. The teeth may be recognised by their silvery whiteness, except in a few cases like Patella and Chiton, where they are of a deep brown colour. When obtained, the radula may be cleaned by boiling in a solution of caustic potash. There is no risk of injury if the solution is not too strong.
“Smaller species may be treated more summarily. The proboscis, the buccal mass, or even the whole animal may be thrown into the potash solution and boiled till scarcely anything is left but the cleaned radula. Remains of animals dried inside the shell may be similarly dealt with, after soaking in clean water. With a little care, this process will answer for shells down to the size of Ancylus or Rissoa. The very smallest (Carychium, Tornatellina, Skenea, etc.) must be crushed on the slide and boiled on it, after removing as much as possible of the broken shell. The radula can then be searched for under the microscope, and washed and mounted on the slide.
“The student must be warned that though the general process is simple, there are difficulties in particular cases. In the Pulmonata, for example, membranes on both sides of the radula need careful removal. Murex, Purpura, and most of the Taenioglossa have the side teeth folded down over the central, so that the arrangement is not well seen till they have been brushed back. The Cones, again, have no basal membrane at all, so that if the potash is not used with great care, the single teeth will fall asunder and be lost. Perhaps the worst case is where a large animal has a radula as small as that of a Rissoa, like Turritella, Harpa, or Struthiolaria, or where the radula is almost filmy in its transparency, like those of Actaeon and the small Scalaria.
“When once the radula is laid out, the mounting is commonly easy. Canada balsam makes it too transparent. Fluids may be used, and are almost necessary for thick radulae like those of large Chitons; but the best general medium is glycerine jelly. It runs under the cover glass by capillary attraction, and may be boiled (though only for a moment) to get rid of air bubbles. It should then be left unfinished for several weeks. If cracks appear, the reason is either that the jelly is a bad sample, or that it has been boiled too long, or (commonly) that the object is too thick; and there is not often any difficulty in remounting. I have no serious complaint of want of permanence against the medium, if I may speak from a pretty wide experience during the last twenty years.”
[323] The substance both of the jaw and radula is neither crystalline nor cellular, but laminated. Chitin is the substance which forms the ligament in bivalves, the ‘pen’ in certain Cephalopoda, and the operculum in many univalves. Neither silica nor keratine enter into the composition of the radula.
[324] τόξον, arrow; ῥάχις, ridge, sharp edge; ταινία, ribbon; πτηνός, winged; γυμνὀς, bare; ῥιπίς, fan; δοκός, beam.
[325] V. concinna, according to Schacko (Conch. Mitth. i. p. 126, Pl. xxiv. f. 5); the lateral is large, strong, unicuspid on a broad base.
[326] In some cases (e.g. Hyalinia inornata) the laterals are very few, while in Zonites laevigatus the first side tooth is more of a marginal than a lateral.
[327] Semon, Biol. Centralbl. ix. p. 80.
[328] According to Moquin-Tandon (Moll. de France, i. p. 44) this process in Bithynia is attached by one end to the wall of the stomach. Vivipara, with two jaw pieces, does not possess this stylet; Bithynia, which does possess it, has no jaw.
[329] J. H. Vanstone, Journ. Linn. Soc. xxiv. p. 369.
[330] Biol. Centralbl. vii. p. 683; SB. Ges. Nat. Fr. 1890, p. 42; Mag. Nat. Hist. (2) v. 1850, p. 14.
[331] νεφρός, kidney.
[332] Ann. Mag. Nat. Hist. (2) xvi. p. 298.
[333] See, for instance, Quart. Journ. Conch. i. p. 340 (Cyl. Raveni): Jahrb. Deut. Malak. Gesell. 1879, p. 98 (Clausilia dubia).
[334] Cailliaud, Journ. de Conchyl. vii. p. 231; Gassies, ibid. p. 44.
[335] Arch. Naturgesch. xlii. p. 209.
[336] Dr. W. B. Carpenter, Rep. Brit. Ass. xiii. p. 71; xiv. p. 1; xvii. p. 93; J. S. Bowerbank, Trans. Micr. Soc. i. p. 123; Ehrenbaum, Zeit. wiss. Zool. xli. p. 1.
[337] See also p. 258.
[338] J. E. Gray, Phil. Trans. 1833, p. 774 f.
[339] J. E. Gray, Phil. Trans. 1833, p. 774 f.
[340] Journ. de Conchyl. iv. p. 424.
[341] Journ. de Conchyl. xii. p. 3.
[342] T. Scott, Journ. of Conch., 1887, p. 230.
[343] M. de Villepoix, Comptes Rendus, cxiii. p. 317.
[344] Proc. Ac. Nat. Sc. Phil., 1892, p. 350.
[345] Mr. B. B. Woodward has recently pointed out (P. Z. S. 1892, p. 528) a very remarkable method of shell absorption and growth in Velates and certain other Neritidae.
[346] The only exception appears to be Pedipes, while in Cassidula and Scarabus the absorption is partial (Crosse and Fischer, Journ. de Conch. xxx. p. 177 f.).
[347] Strombus and Pteroceras (see Fig. [99], p. 200) exceptionally develop a siphonal notch which is distinct from the anterior canal.
[348] The columella, as distinct from the columella lip, is the solid pillar of shell round which the whorls are coiled (Fig. [177]), the lower, or anterior portion of which alone is usually visible.
[349] J. E. Gray, Phil. Trans. 1833, p. 812.
[350] W. H. Dall, Amer. Journ. Sc. xxxviii. p. 445 f.
[351] The term epidermis, as distinct from periostracum, is properly restricted to the outer layer of the skin of the mantle and body generally.
[352] J. Lewis, Proc. Bost. Soc. vi. p. 149.
[353] Journ. of Conch. v. p. 66.
[354] The Dispersal of Shells, pp. 182–195.
[355] E. A. Smith, P. Z. S. 1892, p. 259.
[356] C. T. Musson, Proc. Linn. Soc. N. S. Wales (2), v. p. 883.
[357] Scient. Results Sec. Yarkand Exped. “Mollusca,” pp. 1–16.
[358] Mr. H. W. Kew, The Dispersal of Shells, has brought together a very large series.
[359] The Naturalist in Nicaragua, p. 334 f.
[360] Morelet, Journal de Conch. 1875, p. 194.
[361] Pollonera, Boll. Mus. Zool. Torino, v. 1890, No. 87.
[362] South and south-western France, however, belong to the Mediterranean Sub-region.
[363] The coast-line of north-east China, including Corea and Japan to north Niphon, is much more definitely tropical than the adjacent inland districts. The coast-line, therefore, must be placed in the Oriental Region, while the inland districts belong to the Palaearctic Region.
[364] Biol. Centralbl. ii. p. 208.
[365] Craven, Journ. de Conchyl. (3) xxviii. p. 101.
[366] Jahrb. Deutsch. Malak. Gesell. viii. p. 278.
[367] Netchayeff, Kazan Soc. Nat. xvii. fasc. 5.
[368] Fauna der Congerien-Schichten, p. 142.
[369] Streptaxis is a remarkable instance of a mainland genus. Although abundant in the Oriental, Ethiopian, and Neotropical regions, it never seems to occur on any of the adjacent islands, except in the case of Trinidad (1 sp.), which is practically mainland. Omphalotropis, on the other hand, is the exact reverse of Streptaxis in this respect, occurring all over Polynesia and the Malay Is., as far west as Borneo, as well as on the Mascarenes, but never, save in a doubtful case from China, on the mainland of Asia, Australia, or Africa.
[370] The Amboyna group has been much the better explored. Common to both groups are one sp. each of Kaliella, Trochomorpha, Opeas, Leptopoma, Cyclotus, Helicina.
[371] A. H. Cooke, P. Z. S. 1892, pp. 447–469.
[372] Mysol, with 2 Chloritis, 1 Insularia, 1 Cristigibba, is decidedly Papuan.
[373] See especially C. Hedley, Note on the Relation of the Land Mollusca of Tasmania and New Zealand, Ann. Mag. Nat. Hist. (6) xiii. p. 442.
[374] Hedley and Suter, Proc. Linn. Soc. N. S. Wales (2), vii. p. 613. Twenty-one species are “introduced.”
[375] Nine species have been introduced: 6 from Europe, 2 from the West Indies, 1 from the Western Isles.
[376] It is by no means implied that unbroken land communication between India and Madagascar, across the Indian Ocean, ever existed. A series of great islands, whose remains are attested by the Chagos and other banks, would be quite sufficient to account for the results, as we find them. See especially Medlicott and Blanford, Geology of India, vol. i. p. lxviii.
[377] Journ. Cinc. Soc. Nat. Hist. iii. p. 317. The number is doubtless susceptible of very considerable reduction, say by one-half at least.
[378] Simpson, Amer. Nat. xxvii. 1893, p. 354.
[379] Compare von Martens, Malak. Blätt. 1868, p. 169; von Ihering, Nachr. Deutsch. Malak. Gesell. 1891, p. 93.
[380] The distribution of some Pteropoda has been worked out by Munthe, Bih. Svensk. Ak. Handl. XII. iv. 2, by Pelseneer “Challenger” Rep., Zool. xxiii., and by Boas, Spolia Atlantica.
[381] Bull. Mus. C. Z. Harv. xiv. p. 202; xxiii. p. 34 f.
[382] See papers in P. Z. S. 1878–85.
[383] A break in this uniformity may be found underneath the course of a great oceanic current like the Gulf Stream, which rains upon the bottom a large amount of food. A. Agassiz (Bull. Mus. C. Z. Harv. xxi. p. 185 f.) explains in this way the richness of the fauna of the Gulf of Mexico as compared with that of the west coast of tropical America.
[384] On the western coasts of Europe and America, where the change in surface temperature is very gradual, Purpura lapillus (the west American ‘species’ are at best only derivatives) is able to creep as far south as lat. 32° (Mogador) in the former case, and lat. 24° (Margarita Bay) in the latter, the mean annual temperature of the surface water being 66° off Mogador, with an extreme range of only 8°, and that of Margarita Bay 73°, with an extreme range of only 5°. On the eastern coasts, where the Pacific and Atlantic gulf-streams cause a sudden change of temperature, the Purpura is barred back at points many degrees farther north, viz. at lat. 41° (Hakodadi), surface temperature 52°, extreme range 25°; and at lat. 42° (Newhaven), surface temperature 52°, extreme range 30°.
[385] E. A. Smith, P. Z. S. 1890, pp. 247, 317.
[386] A. H. Cook, Ann. Mag. Nat. Hist. (5) xviii. (1886) p. 380 f; E. A. Smith, P. Z. S. 1891, p. 391 f.
[387] C. Keller, Neue denksch. Schw. Gesell. xxviii. 1883, pt. 3.
[388] According to Tate (Trans. Roy. Soc. S. Austr. 1887–88, p. 70), ‘Australian’ species predominate at Freemantle (32°), but Tenison-Woods (J. Roy. Soc. N. S. Wales, xxii. p. 106) holds that the tropical fauna extends as far south as Cape Leeuwin (34°), and that the Australian forms are not predominant until the extreme south. Tenison-Woods regards Cape Byron (31°) as the limit of the tropical fauna on the east coast, while some characteristic tropical genera reach Port Jackson, and a few (e.g. Cypraea annulus) Tasmania.
[389] A full account of the distribution of Voluta is given by Crosse, Journ. de Conchyl. (3) xix. p. 263.
[390] Usually known as ‘Patagonian,’ but since the Magellanic Sub-region includes a considerable part of Patagonia, and since the greater part of sub-region (6) lies out of Patagonia, it has been thought advisable to change the name.
[391] Amer. Nat. xx. p. 931.
[392] W. H. Dall, Proc. Biol. Soc. Washington, v. p. 1 f.
[393] Trans. Connect. Acad. v. p. 177; Zoologist, 1875, p. 4502.
[394] Rep. Scotch Fish. iii. 1885, App. F, p. 67.
[395] Nautilus, vi. 1892, p. 82.
[396] Journ. Mar. Zool. i. pp. 3, 9.
[397] Rep. Brit. Assoc. 1844, Transactions, p. 74; P. Z. S. 1839, p. 35.
[398] It is convenient, but not morphologically correct, to apply the terms ‘ventral’ and ‘dorsal’ in this sense.
[399] φραγμός, partition; σήπιον, cuttle-bone; χόνδρος, long cartilage.
[400] μυέω, close the eyes; ὕψις, sight; contrasted with Oigopsidae (οἰγω, open).
[401] The classification is that of Foord, Catal. Fossil Cephal. Brit. Mus., 1888.
[402] Saville Kent, Proc. Roy. Soc. Queensland, vi. p. 229.
[403] J. Power, Ann. Mag. N. H. (2) xx. p. 334; P. Z. S. 1836, p. 113; Arch. Zool. Exp. Gén. (3) i. 1893, p. 105.
[404] In deference to Bergh’s high authority, the position of a sub-order is here given to the Ascoglossa. It may be doubted whether that position will stand the test of further investigation, and whether the families concerned will not be added to the Cladohepatic Nudibranchs.
[405] This family has also been classified with the Bulloidea and with the Aplysioidea.
[406] It appears more convenient to treat the whole group together, rather than deal with the two sections separately.
[407] An operculum is said to exist in the young forms of Auricula and Parmacella.
[408] Proc. Ac. Philad. 1892, p. 390.
[409] Compare Jackson, Amer. Nat. xxv. p. 11 f.
[410] “A Monograph of the British Fossil Brachiopoda,” Palaeontographical Society, London, vols. i.-v. 1851–84.
[411] Ibid. vol. vi. 1886.
[412] “Contributions to the Anatomy of the Brachiopoda,” Proc. Roy. Soc., vol. vii.
[413] “Untersuchungen über den anatomischen u. histologischen Bau der Brachiopoda Testicardinia,” Jenaische Zeitschrift, vol. xvi., 1883.
[414] “On a living Spinose Rhynchonella from Japan,” Ann. Mag. Nat. Hist., 5th ser., vol. xvii., 1886
[415] Loc. cit. p. 465.
[416] Shipley, “On the Structure and Development of Argiope,” Mitt. aus d. Zool. Stat. zu Neap. Bd. iv. 1883.
[417] Schulgin, “Argiope Kowalevskii,” Zeit. f. wiss. Zool. Bd. 41, 1885.
[418] American Jour. of Sci. and Arts, 3rd series, vol. xvii. 1879.
[419] Loc. cit. p. 470.
[420] “Recherches sur l’Anat. des Brachiopodes Inarticules,” Arch. Zool. Exp. (2), Tome iv., 1886.
[421] “Untersuchungen über den Bau der Brachiopoden,” Jena, 1892.
[422] “Vorläufige Mittheilungen über Brachiopoden,” Zool. Anz. Bd. viii. 1885.
[423] Hancock’s nomenclature is here used. The corresponding names used by King and Brooks are placed in brackets. Their nomenclature is used by many palaeontologists, and is adopted in Fig. [322].
[424] Development of the Brachiopoda, 1873 (Russian).
[425] “Histoire de la Thécidie,” Ann. d. Sci. Nat., Sér. 4, vol. xv., 1861.
[426] “On the Early Stages of Terebratulina septentrionalis,” Mem. Boston Soc. Nat. Hist., vol. ii., 1869. “On the Development of Terebratulina,” Ibid. vol. iii., 1873.
[427] “Choses de Nouméa,” Arch. d. Zool. exp. et gen., 2nd ser., vol. ix., 1891.
[428] J. Barrande, Syst. Silur. Bohème, vol. v., 1879. Hall and Clarke, Introd. Palaeozoic. Brach. (Palaeont. of New York, 1892–1894). Davidson, Monogr. Brit. Foss. Brach. (Palaeont. Soc., 1851–1884). Waagen, Salt Range Fossils (Mem. Geol. Surv. India, 1879–1885).
[429] The results of the investigations of King (Ann. Mag. Nat. Hist., 4th ser., vol. xii., 1873) and of Brooks (Chesapeake Zool. Laboratory, Scientific Results, p. 35, 1879), and the simple nomenclature of these authors are here followed in preference to those of others, owing to the difference of opinion amongst anatomists of the functions and homologies of the muscles. The lateral muscles enable the valves to move backwards and forwards on each other; the centrals close the shell; the umbonals open it; and the transmedians allow a sliding sideways movement of one valve across the other (see also p. 477).
[430] Davidson and King, Quart. Jour. Geol. Soc., xxx. (1874), p. 124.
[431] Amer. Jour. Science, 1890–1893.
Transcriber’s Notes:
1. Obvious printers’, punctuation and spelling errors have been corrected silently.
2. Where hyphenation is in doubt, it has been retained as in the original.
3. Some hyphenated and non-hyphenated versions of the same words have been retained as in the original.