Marsh — North American Species of Diaptomus. 405 



opodite is near the proximal eiid, the anten- 

 na! process is dentate on the outer margin, Trybomi _ p* ^h(o * 



Right endopodite about equals in length the first 



segment of the exopoxiite, lateral spine median, Judayi — a.'^^^^i'. 



The process of the antepenultimate segment of the 

 right antenna nearly equals or equals the penul- 

 timate segment. 

 The right endopodite equals in length the first seg- 

 ment of the exopodite, spines of the first basal yin n 



segment large, tenuicaudatns — P • ^^ ^ * 



The right endopodite exceeds the length of the 



first segment of the exopodite, spines of the yi o yi 



first basal segment small, sicilis - p < ^^ i ' 



The process of the antepenultimate segment of the 

 antenna exceeds in length the penultimate seg- 

 ment. 

 Large. Lateral spine of the second segment of the 

 male exopodite is terminal or nearly so. 

 The antennal appendage only slightly longer than 

 the penultimate segment, antenaae equal in 



length to cephalothorax, shoshone — p • ^^i ' 



Antennal appendage exceeding in length the ul- 

 timate segment, antennae reaching the furca, Wardt ^ p,'T"33» 



Small. The lateral spine of the second segment of 



the right exopodite is on the proximal half of 



the segment, the antennae reach beyond the 



furca. 



Lateral spine of the second segment of the right 



exopodite short, right endopodite rudimentary, . . . .minutus — p.'> ^«" 

 Lateral spine long, right endopodite equals in 



length the first segment of the exiopodite Ashlandi -^ p/'Tz^Vf 



The antepenultimate segment of the right antenna bears 

 a curved process. 

 The appendage equals or exceeds in length the penul- 

 timate segment. 

 The appendage about equals in length the last two 

 segments, the second basal segment of the 

 right foot is dilated on the inner margin, the 



endopodites are two-segmented Eiseni 



The appendage slightly exceeds in length the penul- 

 timate segment, second basal segment of the 

 right foot -not dilateti on the inner margin, the ^ 



left endopodite one-segmented, franciscanua ~ P< " ' ''' 



The appendage is shorter than the penultimate seg- 

 ment. 

 One CI Ijoth terminal processes of the last seg- 

 ment of the left exopodite are distinctly falci- 

 form. 



. -p.4%1- 



