COPEPODA 



763 



34 (33) Right endopodite of male fifth f(X)t exceeds length of first segment 

 of exopodite, spines of first bas^d scgnu-nts small. 



Diaptumus siciiis Forbes i»8i. 



Found in the GrcAt XaktK f»nnjt 

 the m<)st abundant form laJccn in 

 limnetic ( ollertions; found to M>mr 

 extent in other lake* in the vimc 

 KeneraJ ri^ion. It iv a% a rule, 

 confme*! to the larger and flcrtwr 

 lakes. It is fre«iuently founcl a\m>- 

 ciate<i with I) miniUus l»ut i» read- 

 ily distinKuishe<l by the sJefMlrr. 

 symmetrical, sitkleshaiirtl hcmk 

 terminating the cxofM^lite trf the 

 riRhl fifth f<K»t of the male; thi* it 

 not a characteristic, h«iwever, that 

 will distinguish it frc)m s{irc>cs 

 found in other Ifnalities. 



Lenjjth of fem;iJe. 1 js mm 

 Length of male, i i <; nun 



Fig. 1 189. Diaptomus siciiis, male. A, terminal segments of 

 right antenna. X 194. B. fifth feet. X i94- (Original.) 



35 (27, 32) Process exceeds in length penultimate segment 36 



36 (39) Large. Lateral spine of second segment of exopotlite of right fifth 



foot of male terminal or nearly so 37 



37 (38) Process of antepenultimate segment of right antenna of male only 



slightly longer than penultimate segment, antennae equal in 

 length to cephalothorax. 



Diaptomus slwshonc Forbes 1803. 



Rocky Mountains. Not so wi<1«prr*d 

 or characteristic of the mountain lakes ai 

 D. Tyrelli Popix-, althou>:h this K>ant n|*^ 

 cics is by no means uncommon, juul i* e>|^- 

 ciaily striking because commonly colortd • 

 brigiit red. 



IxMigth of fem.ile. J 9 mm. 



Length of male, i.5 mm. 



Fig. 1190. Diaptomus Shoshone, ma\e. i4, fifth feet. 

 X 108. B, terminal segments of right antenna. 

 X 180. (Original.) 



