THE WATER FLEAS (CLADOCKRA) 



691 



II (12) Reflexed antenna not reaching posterior margin of valves. 



„,„„,,:. Diaplianosoma brachyurum (Lieven) 1848. 



Eye pigment large; eye filliuK end of head. Color yd- 

 lowish-transparent. Length. V . oS-o.g mm.; ^.ca. 04 

 mm. Common in marshes ami wec<ly margins of Ukr^ 

 Very probably the next s|K'cics is merely a limnetic van 



ety of this. 



Fig. 1054. Diaphanosoma bra(hyurum. 



O.I MM. i 



12 (11) Antenna when reflexed reaches or exceeds posterior margin of valves. 



Diaphanosoma Icuchtcnbcrgianum I-'i.scher 



1850. 



J^-^ 



^ (f^m^^^- 



Eye not filling end of head, pigment small. 

 Color hyaline. Length. V , o.<>-i.i mm.; ^ . to 

 0.8 mm. Common in open waters of lakes 



Fig. 1055. Diaphanosoma Uucklrnbergu 



13 (10) Spines on post-abdomen U 



14 (17) Eye dorsal, far from insertion of antennule and optic ganglion. No 



rostrum Latonopsis Sars i^^i^ . . 15 



No tongue-shaped process on ventral side of head, or antennary expansion. Otherwise much 

 like Latona parviremis. Posterior margin of valves with ver>- long setae (often lost). 6 with 

 long antennule, copulatory organ, and hook on first foot. 



15 (16) Shell gland drawn out into very long posterior loop. 



Latonopsis occidental is Hirge kSqi. 



Post-abdomen with about 9 small anal spines. Color yellowirJi-trans- 

 parent. Length, ? , to i .8 mm. ; ^ , ca. o.O mm. New Lngbnd lo Colorado 

 and Texas; in weedy pools and lakes. 



^^^^^.IbK^ , yV^ 



O^ MM 



^ 1 ' \V ' , Figs 1056, 1057 . h. LaUmopns pctidtntHu 

 \ / , (Sec alio Fig 1057 J 



i 



