112 THE ROTIFERA. 



Family IV. ADINETAD/E. 



Corona a flat, prone surface ; ciliary wreath the furred ventral surface of the 

 corona ; trophi ramatc ; frontal column soldered to dorsal surface, and ending in two 

 hooks. 



The family Adinetada lias been formed to receive one genus, which itself contains 

 at present only one species. It has been separated from the Philodinadce on account of 

 its lacking the usual corona of two circlets, and of its having in lieu of it a mere furring 

 of a flattened, ventrally placed, portion of the head, which in some degree resembles 

 the face of the genus Proales. In other respects the organization is that of the Calli- 

 dince, except that the frontal column, which is so striking a feature in the other Philo- 

 dinadcB, and which is tossed aside like a hood when the coronal wheels are expanded, 

 is here soldered as it were to the dorsal surface, and projects slightly beyond it, bearing 

 two curved hooks. 



Genus ADINETA, Hudson. 

 GEN. CII. Eyes absc?it. 



A. vaga, Davis. 

 (PL X. fig. 10.) 

 Callidina vaga .... Davis, Mon. Micr. J. vol. ix. 1873, p. 201, pi. xiv. 



SP. CII. Body smooth, colourless, with longitudinal corrugations ; spurs short, 

 finely pointed ; teeth two. 



This species was discovered by Mr. H. Davis in 1867, along with abundant speci- 

 mens of P. roseola, in a parcel of pink dust sent to him by the Rev. Lord S. G. Osborne, 

 and found in some open stone vases in Lord Osborne's grounds at Blandford. These 

 vases, at times, become partly filled with rain, and the wind drives into them dead 

 leaves and other matters, which by their decomposition seem to afford suitable food. 



The front of the head is somewhat like a thumb in outline, and on its dorsal surface 

 is what appears to be the trace of a column soldered to the head, projecting slightly 

 beyond it, and bearing two transverse hooks. The corona, though nothing but the flat 

 ventral surface of the head, yet shows a sort of division into two parts, owing to the 

 absence of cilia on a broad median line leading to the buccal funnel : the rest of the 

 surface is densely furred with minute cilia. The base of the corona, just at the animal's 

 neck, rises on either side above its general plane, and forms a well-marked ridge. Mr. 

 Davis says that each ridge is strongly serrated, and draws them with teeth pointing 

 forwards. I could see no such serrations, though the strong cilia, that here lead to the 

 entrance of the buccal funnel, frequently produced a fleeting appearance of serration : 

 but all my specimens were small and young, and possibly the serrations were not yet 

 developed. The pathway (if it may be so termed), through the coronal cilia, leads 

 straight to a long buccal funnel imbedded in a thick fleshy mass, and ending at the 

 niastax, each ramus of which bears two main teeth and a multitude of fine parallel 

 stria?. 1 When Adineta is feeding, it curves the flat corona so as to bring its two furred 

 halves opposite to each other, and at the same time draws together the transverse 

 ridges at its base. In this way a ciliated semi-cylinder is formed as a prolongation of 

 the buccal funnel, and minute atoms may be seen rapidly streaming down the tract 

 clear of cilia, into the funnel's entrance. The stomachs of my specimens were all filled 

 with clear yellowish particles, but of what substance I could not make out. I could see 

 no salivary or gastric glands, but the foot-glands were conspicuous. The contractile 



' Mr. Davis measured these, and found there were from thirty to forty thousand in the inch ; in 

 my specimens the stria? were about fifty thousand to the inch. 



