THE WATER FLEAS (CLADOCERA) 



705 



73 (74) Valves smooth; ephippium reticulated around edges, smooth in 

 -^ middle; antennules of male with sense seta near middle. 



Moina rectirostris (Ley dig) 1860. 



Colorless, or with bluish cast. Head extended or little depressed; deep cervical and supra- 

 ocular depressions. Post-abdomen with long 

 projection and 1015 post-anal spines and 

 bident. Claws pectinate. Antennules of $ 



with 5-6 hooks at apex. Length, 9 . 



mm.; $ , 0.4-0.6 to i.o mm. 



Widely 

 uted; in 

 pools. 



distrib- 

 muddy 



FIG. 1092. Male antennule. A, Moina rectirostris. 

 C, M, macrocopa. 



0.1 MM. i 1 



FIG. 1093. Ephippium. A, Moina 

 rectirostris. B, M. affinis. C,M. 

 macrocopa. (A and C after Lfllje- 

 borg.) 



74 (73) Valves striate; ephippium reticulated all over; antennules of male 



with sense seta near base. . . . Moina affinis Birge 1893. 



O OS MM i ' Much like M. rectirostris, from which the 



young 9 are hardly distinguishable. Anten- 

 nules of $ broad, fringed with fine hairs on 

 inner margin; 4-6 hooks at end. Length, 9 

 0.8-1.0 mm.; $ , 0.3-0.6 mm. 



Wisconsin to Louisiana. 



M . rectirostris, affinis, and brachiata have 

 been often confused in faunal lists. 



FIG. 1094. Moina affinis, apex of post-abdomen. 



/ 



75 (70) No supra-ocular depression; claws not pectinate; antennules of male 



with sense seta in middle or below; first foot of male 

 with long flagellum. . Moina macrocopa Straus 1820. 



Not very transparent; yellowish or greenish. Head extended. 

 Terminal part of post-abdomen long, with 10-12 spines besides 

 bident. Two ephippial eggs. $ with elongated head; 5-6 hooks 

 on antennule. Length, 9 to 1.8 mm.; $ , 0.5-0.6 mm. 



Pools, Wisconsin, Nebraska, Colorado, N. Dakota; doubtless 

 widely distributed. 



This species is M. paradoxa Weismann and M . flagellata Hu- 

 dendorf. 



FIG. 1095 Moina macrocopa. 



0.2 MM. 



