TWO NEW iPEClKS OK MA<,'ROTRA0HEI-0US CALLIDIN^. 197 



relationsliip, however suitable that name should otherwise 

 appear. 



The second point is the use by Dr. Hudson of the term 

 oesophagus in the specific characters given (Supp., pp. 9-10) for 

 Gallidina symbiotica and C. Leitgehii. The former he states to 

 possess an " oesophagus without a loop," the latter, an " oeso- 

 phagus with a loop." The portion, however, of the alimentary 

 tract where the loop is present in G. Leitgehii, is that between 

 the mouth cavity and the mastax, and is better identified as the 

 buccal funnel, gullet, or pharyngeal tube, whereas the oesophagus 

 is that portion following the mastax, and through which the 

 food is conducted in its passage from the mastax to the 

 stomach. As Dr. Hudson himself (Rotifera, i., p. 7) has 

 defined it in this sense, his use of it to denote the pharyngeal 

 tube is clearly a slip. 



Gallidina symhiotica, therefore, has the pharyngeal tube 

 without a loop, and G. Leitgehii has the pharyngeal tube with 

 a loop. So far as I am aware the loop occurs in no other 

 species of the genus. 



The occurrence of two more specimens of Gallidina spinosa 

 enables me to add to my former description of that species that 

 the rami have respectively three and two teeth, giving the 

 formula f, and that the species is viviparous. The latter 

 character, although possessed by several of the commensal 

 Callidinee, has not yet been noted among the macrotrachelous 

 group, and the doubt is thereby raised as to whether the species 

 is not in reality a Philodina, in which the eyes have escaped 

 detection. I hope, therefore, that whoever may next find it will 

 look closely for the eyes, for the number of toes, -and for the 

 presence of a foetus. In Philodina the eyes are frequently very 

 difficult to see, from the paleness of. the colouring matter ; and 

 as this species has a very rough and opaque skin, it is the more 

 possible that they may have escaped my search. 



The two new species exhibit extreme departures from the type 

 of ciliary organs normal among the Philodinadfe. For my present 

 purpose that type may be said to consist of two ciliary wreaths, 

 of which the principal is borne round about the peripheries of 

 the dilated and cushion-like tops of two prominent fleshy lobes, 

 placed side by side, and separated by a conspicuous gap. In a 

 directly dorsal view, one observes at the outer lateral bases of 



