The Rotatorian Genus Diaschiza. 131 



The toes are stiff and decurved, ending in a sharp point, and 

 are nearly always carried wide apart, when the points are seen 

 from a dorsal view to curve in slightly towards one another. 



The gastric glands are somewhat large, but never tinted. 



The jaws are very striking owing to the exceptionally large and 

 long incus which ends in a decided fulcrum. They never protrude 

 through the buccal orifice. 



It feeds on flocculent matter, not on diatoms, and often fills its 

 stomach with a brown mass of food studded with fat-globules. 



Size. — Total length y^ in. (194 fi) : toes alone 5 ^ Ti in. (47 /u.) ; 

 breadth g| 5 in. (67 /a) ; height ¥ f z in. (53 //,). 



Common. 



The Male, PI. II. fig. 55. — This sex occurred in water from 

 Knowsley Park on November 15, 1901, in several examples. It 

 has the four plates, the usual clefts between them, and the cervical 

 eye exactly as in the female. 



Like the males of many rotifers (but unlike that of D. gibbet) 

 its length is very small compared with that of the female, being 

 little more than half, whereas the male of D. gibbet is £ of the 

 female in length. 



The toes are fairly long in proportion to the trunk, thin and 

 decurved. 



It is without manducatory organs, the sperm-sac filling the 

 greater part of the trunk. 



In habits, it is very restless, contorting itself into all sorts ot 

 shapes and sizes. The figure represents the most normal shape 

 and attitude. 



Size. — Total length g^ in. (113 fi) ; toes alone ^y in. (27 fi) ; 

 breadth ^^ in. (30 /x) ; height -gfa in. (27 /*). 



Kare. 



Diaschiza Derbyi sp. n. 

 PI. IV. figs. 13, 13a, and 135. 



Spec. Char. — Body ovate cylindrical, laterally compressed ; 

 head sub-conical ; neck a slightly marked constriction ; face sub- 

 prone ; corona extending well down ventral surface ; lorica not 

 unusually flexible ; dorsal cleft well marked ; lateral cleft wide, 

 well marked ; eye cervical, on dorsal extremity of brain lobe, with 

 one, sometimes two, clear spheres in front; foot short, flexible, 

 terminal; toes about £ length of rest of body, nearly straight, 

 slightly upcurved, often thrown up over back. 



This species appeared in small numbers in the lake and in a 

 pond in Knowsley Park, Lancashire, at various times throughout 

 the winter of 1900-1901, until May of the latter year, when it 



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