[71] See also the descriptions given by Dujardin (Ann. des Sci. Nat. 1851, v. xv.) and Claparède (Anat. und Entwickl. der Wirbel osen Thiere) of the interesting genus _Echinoderes_, which these two eminent naturalists unite in regarding as intermediate between the Annelides and the Crustacea. [72] “On a New Rotifer.” _Monthly Microscopical Journal_, Sept. 1871. [73] Generelle Morphologie, vol. ii. p. 79. [74] Monographie der Moneren, p. 43. [75] Gegenbaur. Grund. d. Vergleich. Anat. p. 210. See also Dr. M. S. Schultze, Beiträge zur Naturg. der. Turbellarien. 1851. Pl. vi. fig. 1. [76] Monographieder Moneren, p. 10. [77] See Kauffmann, Ueber die Entwickelung and systematische Stellung der Tardigraden. Zeits. f. Wiss. Zool. 1851, p. 220. [78] It is true that among the Insecta generally the first stages of development differ in appearance considerably from those above described; those of _Platygaster_, as figured by Ganin (ante Figs. 17-22), being very exceptional. [79] Monograph of the Gymnoblastic or Tubularian Hydroids, by G. J. Allman, Ray Soc. 1871, p. 86. [80] Mém. sur les Vers Intestinaux, 1858. [81] Natural History Review, 1861, p. 44. [82] Ann. des Sci. Nat. 1847, p. 90. [83] Fauna littoralis Norvegiæ, pl. viii. [84] Trans. of the Microsc. Soc. of London, 1851. [85] Quarterly Journal of Microsc. Science, 1853. [86] Wiegmann’s Archiv., 1840, p. 196. [87] Ueber die Erzeugung von Schnecken in Holothurier. Berlin, Bericht, 1851. Ann. Nat. Hist. 1852, v. ix. Müller’s Archiv., 1852. [88] Natürliche Schöpfungsgeschichte, pl. x. [89] Ann. des Sci. Nat. 1853, p. 89. [90] Ann. des Sci. Nat. 1857, pl. vi. [91] Cyclopædia of Anatomy and Physiology. Art. Ovum, p. 4. [92] Thomson, loc. cit. Article, Ovum, p. 139. THE END. RICHARD CLAY AND SONS, LIMITED, LONDON AND BUNGAY. BY THE SAME AUTHOR. PRE-HISTORIC TIMES. As Illustrated by Ancient Remains and the Manners and Customs of Modern Savages. Fifth Edition. 8vo. 18_s._ (Williams & Norgate.) THE ORIGIN OF CIVILIZATION AND THE PRIMITIVE CONDITION OF MAN. Fifth Edition. 8vo. 18_s._ (Longmans, Green & Co.) MONOGRAPH OF THE COLLEMBOLA AND THYSANURA. 1871. (Ray Society.) ON BRITISH WILD FLOWERS CONSIDERED IN RELATION TO INSECTS. Illustrated. Fifth Edition. Cr. 8vo. 4_s._ 6_d._ (Macmillan & Co.) ADDRESSES, POLITICAL AND EDUCATIONAL. 8vo. 8_s._ 6_d._ (Macmillan & Co.) SCIENTIFIC LECTURES. Second Edition. 8vo. 8_s._ 6_d._ (Macmillan & Co.) FIFTY YEARS OF SCIENCE. Being the Address delivered at York to the British Association, August, 1881. Third Edition. 8vo. 2_s._ 6_d._ (Macmillan & Co.) CHAPTERS IN POPULAR NATURAL HISTORY. 12mo. 1_s._ 6_d._ (National Society.) ANTS, BEES, AND WASPS. With Illustrations. Ninth Edition. Crown 8vo. 5_s._ (Kegan Paul, Trench & Co.) ON REPRESENTATION. Fifth Edition. Crown 8vo. 1_s._ (Swan Sonnenschein, & Co.)