14 Transactions of the Society. 



Diaschiza ventripes Dixon-Nuttall. 

 PL II. fig. 7. 



BIBLIOGRAPHY. 



Dixon-Nuttall, F. E. — On D. ventripes, a new Eotifer. Jonrn. Qnek. Micr. 

 Club, London, April 1901, p. 25, pi. 2, figs. 1-3. 



Spec. Char. — Body almost cylindrical, dorsum arched, venter 

 slightly concave ; head separated by slight constriction, deflexed ; 

 neck well marked on dorsal surface ; face sub-prone ; corona ex- 

 tending down ventral side of head ; lorica normal Diaschiza type, 

 projecting over base of foot; dorsal cleft well marked, narrow, 

 deep, straight, widening a little aft; lateral cleft well marked, 

 rather wide ; eye cervical, double, on the end of brain ; foot short, 

 ventral ; toes about \ length of rest ol body, short, sharp, slightly 

 decurved. 



This species was described in the Quekctt Journal (loc. cit.). 

 Since then we have had great quantities of specimens from many 

 ponds in this neighbourhood. 



On further acquaintance it turns out to be at times as large as 



ih in - ( 133 /*)- 



One of the leading features about this rotifer is its arched back, 

 which gives a bent form to the whole body. This, and the 

 ventrally situated foot, are very striking. 



The lorica has the appearance of being too large for the trunk, 

 culminating in a clear projection over the foot. 



The face is really sub-prone relatively to the head ; but as the 

 whole head is depressed by the curvature of the body, it appears 

 quite prone. 



The lorica and its clefts are normal. 



The eye consists of a pair of red pigmented, hollow hemi- 

 spheres, fused together at their point of contact. 



The foot is short and distinctly ventral. 



The toes are remarkably constant in shape and length in this 

 species, being somewhat short and stout and slightly decurved. 



The jaws have the incus short, very stout, and specially 

 widened at the fulcrum. 



The food consists mainly of diatoms, but also of flocculent 

 matter. 



It is slow and graceful in its habits, and seldom found swim- 



ming. 



The general curve of the body, the projecting lorica, the double 

 eye, the ventral foot, and the short stout incus, mark this species 

 as very distinct from D. Hoodii and the rest. 



Size. — Over all j^q in. (133 p) : toes alone g^ in. (27 //.) ; 

 breadth g^ in. (42 /x) ; height ^^ in. (53 //,). Well distributed 

 in Lancashire ponds. 



\(Continucd on p. 129.) 



