166 
IOWA ACADEMY OP SCIENCES. 
Note. “Since writing the above upon D. retrocurva the 
“ Kevision of the Genus Daphnia,” by Jules Richard of Paris, 
has been published, in which D. retrocurva is recognized as a 
species because of pigment- spot and caudal claw characters, 
and D. keruses as a synonym of it. 
Fig. 5. (a) Oeriodaphnia acanthinus, n. sp. (b) Daphnia hybus, n. sp. (c) Daph- 
nia hybus, post abdomen. 
Note— The reticulations in a are somewhat too regular. 
