270 Binocharis Oollinsii. 



left isolated when it is suddenly retracted. The front is set 

 with strong cilia, which in action produce a vigorous vortex on 

 each side. 



The foot consists of four joints, of which the first is thick, 

 and carries at its extremity on the dorsal side a pair of diver- 

 gent spines ; the second joint is very short, and slenderer ; the 

 third is longer, but still further attenuated, expanding slightly 

 at the tip ; the fourth consists of two straight, slightly de- 

 curved, moderately long, spine-shaped toes. 



An eye of conspicuous size, transversely crescentic in form, 

 and of rich ruby hue, is seated just in front of a large globose 

 mastax, which displays the ordinary structure. I have not 

 been able to discern the cerebral mass on which the eye, 

 doubtless, rests. The alimentary canal is ample, commonly 

 filled with the digestive secretions, of a clear yellow-brown 

 hue, and with granular food. The viscera are difficult of 

 exact definition, from the complex nature of the integument, 

 and its appendages ; but seem to present no remarkable 

 feature. 



This very attractive form was brought under my notice 

 nearly a year ago by Francis Collins, Esq., M.D., Assistant 

 Surgeon in the Royal Military College, Sandhurst. He kindly 

 communicated specimens to me, from which the preceding 

 description, and the accompanying figures were prepared. As 

 the species appears to be hitherto unrecognized, I honour it 

 with the name of its discoverer. Dr. Collins favours me with 

 the following notes concerning it : — 



"The new species of Dinocharis is [found] in the parish 

 of Sandhurst, in Berkshire, and as yet only in one small 

 pool in a fir wood between the Eoyal Military and Wel- 

 lington Colleges, about two miles from the former and 

 one from the latter. The pool is not more than eight feet 

 in length by five in breadth, and from four to five in depth. 

 It receives the surface drainage of a very small portion of the 

 wood. The drains are open, and are almost choked with moss, 

 and it is chiefly in one of these, close to the pool, that this 

 interesting and curious species has been found. Both the pool 

 and the drains are peculiarly rich in rare species of Rot&fera. 

 They contain also many varieties of Diatoms, Desmids, Infu- 

 soria, and indeed microscopic objects without number. 



" The history of our little creature is rather curious. In 

 September, 1861, a lady (Miss S.) was staying with me. On 

 leaving my house she took away a bottle of water from our 

 favourite little pool, which proved to contain specimens of our 

 new Dinocharis. It was not until the autumn of last year that 

 I for tho first time saw a specimen, but then I found it in 

 abundance. In the winter it disappeared entirely. In April 



