

CHAPTER VIII 



ROTIFERA, GASTROTRICHA, AND KINORHYNCHA 



ROTIFERA HISTORY EXTERNAL FEATURES MOVEMENT ANATOMY 

 REPRODUCTION EMBRYOLOGY CLASSIFICATION DISTRI- 

 BUTION AFFINITIES GASTROTRICHA KINORHYNCHA 



The Eotifera are microscopic animals, the largest not exceeding 

 one-eighth of an inch in length. According to Hudson and 

 Gosse, 1 they are first recorded in an observation of the Eev. John 

 Harris, in 1696, of "an Animal like a large Maggot which could 

 contract itself into a Spherical Figure, and then stretch itself out 

 again ; the end of its Tail appeared with a Forceps like that of 

 an Ear-wig" 2 This was certainly a Bdelloid Eotifer. 



In 1703 Leeuwenhoek 3 gave a fuller description of a tubico- 

 lous form, probably Zimnias, and noted the peculiar appearance 

 of the ciliary wreath as " two wheels thickset with teeth as the 

 wheel of a watch." He also noted a little later 4 the way in 

 which Melicerta (see p. 206) builds its tube, and was the first to 

 observe the revivification of certain species after drying. 5 Joblot, 

 a French professor of mathematics, in 1718 figured and described 

 a large number of new genera and species with more or less 

 fantastic details. Baker's figures 6 are a considerable advance on 

 Joblot's, and his descriptions of habits are still fresh and accurate. 

 Eichhorn found a number of new and interesting forms ; and 0. 

 F Miiller, influenced by the new discipline of Linnaeus, not 



1 The Eotifera, two vols, and supplt. London, 1886-89. 



2 Phil. Trans, vol. xix. No. 220, p. 254 (abridged ed. vol. iii. 1705, p. 651). 

 8 Ibid. vol. xxiii. No. 283, p. 1304 (abridged ed. vol. v. p. 6). 



4 Ibid. vol. xxiii. No. 295, p. 1784 (abridged ed. vol. v. p. 175). 



5 Ibid. No. 337, vol. xxviii. 1714, p. 160. 



6 Employment for the Microscope. London, 1785. 



