6io 



FRESH-WATER BIOLOGY 



1 iii- 938. Apsilus bucinedax Forbes 

 Ventral view. X65. (After Stokes.) 



Fig. 9.57. Stephanoceros eich- 

 hormi Ehr. X 60. (Aftet 

 Weber.) 



Fig. 939. Atrochus tenlacutatus 

 Wierz. X 35. (After Wierzejski.) 



Hg, 941. Acyctus in- 

 quietus Lcidy. X 12. 

 (After Leidy, from Hud- 

 son and Gosse.) 



Fig. 940. Pompholyx 

 complanata Gosse. 

 X24S. (After Hud- 

 son and Gosse.) 



Fig. 942. Pterodina patina Ehr. A, Dorsal view of female. 

 X 225. (After Weber.) B, Dorsal view of the male. (After 

 Marks and Wesch^.) C, Corona, showing the two wreaths of 

 cilia. (After Wesenberg-Limd.) 



