236 TROCHELMINTHES 



Key to the families of Illoricata here described: 

 Oi No foot present ; animals transparent, short and more or less spherical. 



bi Animals spherical with a ring of cilia near equator 1. TROcnosPii^RiDAE 



ba Body sac-shaped. 



Ci No long lateral appendages 2. Asplanchnidae 



a. Long lateral appendages present with which the animal jumps. 



3. Triartiiridae 

 Ca Foot with 2 toes present. 



bi Corona with 3 to 7 large prominences with setae 4. Hydatinidae 



62 Corona without these ; body elongate, often with a pair of ciliated pro- 

 jections (auricles) 5. Notommatidae 



Family 1. TROCHOSPHiERIDAE. 



Spherical rotifers without corona or foot and with an encircling 

 band of cilia near the equator or towards the forward pole; mouth 

 ventral and anus at the hinder pole; the viscera are in the hinder hemi- 

 sphere: 1 genus. 



Trochosph^ra Semper. With the characters of the family: about 

 3 species. 



T. solstitialis Thrope (Fig. 376). Band of cilia between equator 

 and forward pole; diameter 2 mm. : in the Illinois River and at Put-in-Bay, 



Lake Erie; Asia. 



Family 2. ASPLANCHNIDAE. 



Large transparent sac-shaped rotifers, without anus and usually 

 pelagic: 3 genera. 



1. AsPLANCHNA Gosse. Foot absent; jaws large; animals vivipa- 



6--T 



4 

 Fig. 370 Fig. 377 Fig. 378 



Fig. 376 — Trochosphcera solstitialis (Delage et Herouard). 1, brain; 2, mouth; 

 3, kidney tubule ; 4, anus ; 5, intestine ; 6, ovary ; 7, dorsal nerve. IMg. 377 — 

 Asplanchna herricki (from Sussw. F. Deut). Fig. 378— PolyartJira platyptera (from 

 Siissw. F. Deut.). 



rous, the embryo being frequently seen in the mother ; 1 or 3 eyes present ; 

 corona with two slight elevations: about 7 species. 



A. priodonta Gosse. Body without humps and barrel-shaped; eyes 

 3; length .5 mm.: often very common; pelagic. 



A. herricki* De Guerne (Fig. 377). Body amphora-shaped ana 

 without humps; eyes 3: pelagic. 



• See "Early Development of Asplanchna herrickii," by H. S. Jennings, Bull. 

 Mus. Comp. Zool., Vol. 30, 1896. 



