398 OHIO BIOLOGICAL SURVEY 



dusky (Landacre). Landacre also notes a variety "with spines 

 on the ends and smooth in the middle" which may possibly be re- 

 ferred to subarmata. 



Hamilton, O., storage reservoir. 



44. T. obtusa Palmer (Fig. 4, PI. XXI). 



Cylindrical, broadly rounded anteriorly and conical poste- 

 riorly; thickly covered with spines; flagellum opening narrow; 

 flagellum(?). 



L. 33;u. D. 16jU,. 



Distribution, North America. Ponds and ditches. 



45. T. horrida Palmer (Fig. 5, PI. XXI). 



Broadly oval, covered with numerous spines with nearly par- 

 allel margins and abruptly pointed at ends ; minute wart-like pro- 

 cesses between base of spines; collar low with widened mouth, 

 the margin undulating; flagellum ( ?). 



L. 40^. D.(?). 



Distribution, North America. Ditches. Obtained in N. J. by 

 Palmer and in Iowa by Edmundson. 



46„ T. saccata Lemm. (Fig. 6, PI. XXI) . 



Oval, gradually narrowed anteriorly into a neck -like process; 

 covered thickly with spines; flagellum (?). 

 L.(?). D.(?). 

 Distribution, Paraguay, S. A. Swamps and bogs. 



47. T. bulla Stein (Fig. 7, PI. XXI) . 



Elongately oval, covered with short spines, scarcely narrower 

 posteriorly with distinct collar (6/i in height) provided with 

 teeth ; flagellum about length of body. 



L. 50-5 V D. 20/x(?). 



Distribution, cosmopolitan ( ?). Standing water. 



Var. regularis Lemm. without spines, emarginate anteriorly, 

 neck absent. L.30/x. D.14/x. 



48. T. obovata Stokes (Fig. 8, PI. XXI) . 



Oval, gradually narrowed posteriorly, thickly covered with 

 short spines; flagellum opening with annular thickening; fla- 

 gellum (?). 



L. 22.6|u. D.(?). 



Distribution, North America. Swamps and bogs. 



