Dr. C. T. Hudson on Rhinops vitrea. 27 



IX. — On Rhinops vitrea, a new Rotifer. 

 By C. T. Hudson, LL.D. 



[Plate II.] 



I FOUND a solitary specimen of this creature in a pond at the 

 back of the mansion in Losely Park, near Guildford, some five 

 years ago, and had only just made a rough sketch of it when 

 I was called away from my microscope, and lost the Rotifer 

 from the drying up of the water. Although I returned several 

 times to the same pond, I never could succeed in finding any 

 more specimens ; but last week I captured scores of them in a 

 pond in Garraway's Nursery Gardens, at Bristol. 



This is an illoricated Rotifer, with its ciliated wreath divided 

 into several series : it belongs therefore to the Hydatinea ; but 

 its two eyes set in a sort of proboscis forbid, I think, its being 

 ranked under any of the genera given in Pritchard. I appre- 

 hend, therefore, that it will have to be placed in a new genus, 

 which I venture to name Rhinops, as well as to give to this 

 species the title vitrea, from its glassy cuticle. 



The trochal disk has two parallel lines of cilia running 

 round it from the foot of the proboscis to the buccal funnel, 

 the ventral side of the upper portion of which is formed by a 

 projecting fold of the cuticle, as is shown at PI. II. fig. B, a. 

 The cilia of the inner row are the larger, and are sometimes 

 held erect ; from their bases the substance of the disk slopes 

 downwards and inwards, so as to form a hollow inverted trun- 

 cated cone like the glass in a beetle-trap. The smaller and 

 lower end of this cone is the aperture of a large cavity, whose 

 only other opening is the buccal funnel. 



The proboscis (PI. II. fig. A, b) is ciliated all over its ventral 

 surface and its edge, except at the extreme point ; it carries 

 also two brilliant-ruby eyes. The buccal funnel and the large 

 wedge-shaped aperture above it are also richly ciliated ; but I 

 could not detect any cilia on the truncated cone. 



I have frequently seen objects swept into the cavity, and so 

 down the buccal funnel to the mastax, and have noticed how 

 skilfully the ciliated proboscis directs the atoms down the 

 cone. 



Rhinops usually swims at a moderate pace, rolling gently 

 round its longer axis as it goes ; and every now and then it 

 bends its proboscis over towards its back (thus fully displaying 

 the cilia), and turns somersets, as Synchceta does, only in a 

 much more leisurely manner. Occasionally, however, it darts 

 suddenly forward ; and at each time that I have watched it 

 doing so, I have fancied that I saw the atom which it wished 

 to secure ; certainly the impression produced on my mind was 



