THE OSTk.\( ODA 



809 



21 



Second antenna five-segmented in l)oth si-xes. Second leg U-nnl- 

 nating in one claw and one rdU-xcd st-ta (I-jk. i.-yOb). 



Only one species found ni Aorlh Anurici. 



Cyprois tpuirf^inoia Strautt l8>|. 



I^nKth 1. 5.1 ram., bmfilh avf 



mm 1. . -I- - ' I ■ ' - ' - 



vdl, 

 less 



water. ^ 



moniuha 1 



ments. Ma> . 



lorn (leljris. d: 



later dry up. S« > 



sli^'htly curvr«l; 



miinly loriK- .^1 



caRO, III. (Jack:»jii l^t.,. A^il. 



May, June. 



Fig. I :<,»', 

 Cytrois martinala : 

 tcmalc, X i^; 

 X ?«;: (<•) hur 

 (<i) .Maiillary «, 





22 (2.^) Natatory setae of the second antennae entirely lacking (Fig. i:c>S c). 



Subfamily Ca.ndunlnak . . 91 



23 (22) Natatory setae of the second antennae very evident, usually extend- 



ing at least to tips of terminal claws (Figs, i :(*s e and 

 1290 c) 24 



24 (25) Terminal segment of second leg with three long setae and no claws, 



— one seta reflexed (Fig. 12 58 /)). 



Ilyocypris Brady and Norman 1S89 . ^6 



25 (24) Terminal segment of second leg with at least Dnc claw (Fig. 



12686), — and usually beak-shaped iS 



26 (27) Shell with many prominent tubercles, knobs, and furrows. Nata- 



tory setae reaching to tips of terminal claws, or slighUy 

 beyond Ilyocypris gibba KAV\\y\*Mr \^-^^ 



Length 0.85 to 0.05 mm. Shell much tuhftoiUl* 



anteriorly and posteriorly, and dct-idc<JK fv:rT..»rvl 

 anterodorsally. Two prominent tiil»cr. 

 of the eye siH.t. Poor swimmer* _ \ 

 straight, its terminal k\.: 

 plain. Termiii.il M-ta 



of torminaUlaw. Sw.i . .n , , . . 



the spring months. In .omj^ay wiiii /. .'yjJ; ». usu- 

 ally. Colorado, March. 



Ftc i:c7 



Ilyocypris tihhc. <J^ Skk virw. X 4S: 



(ft) Donil view, X 44. 



