772 FRESH- WATER BIOLOGY 



67 (70) First segment of exopodite of male fifth foot without hyaline 

 appendage 68 



68 (69) " Right endopodite of male fifth foot triangular in form, first ab- 

 dominal segment of female has digitiform process on right 

 posterior border Diaptomus nudus Marsh 1904. 



Found in lakes near Pike's Peak, 

 Colorado. 



Length of female, 1.132 mm. 

 Length of male, 1.115 nim. 



FIG. 1207. Diaptomus nudus. A, fifth feet of 

 male. X 105. B, abdomen of female. X 105. 

 (Original.) 



69 (68) In male fifth foot, second basal segment with hyaline appendage 

 on inner margin, first segment of right exopodite with trans- 

 verse ridge, second segment with oblique ridge and hyaline 

 process near the outer margin. 



Diaptomus purpureus Marsh 1907. 



Found in Cuba. This is a conspicuous species, both on account of 

 the large size and the purple color of the furcae, furcal setae, and distal 

 ends of the antennae. 



Length of female, 2.56 mm. 



Length of male, 2.24 mm. 



FIG. 1208. Fifth feet of male Diaptomus purpureus. X 76. (Original.) 



