COPEPODA 



761 



27(32,35) Process much shorter than penultimate segment 28 



28(31) Right endopodite of male fifth foot rudimentary 29 



29 (30) Lateral spine of second segment of right exopodite of male fifth 

 foot terminal Diaptomus lintoni Forhea i&gs. 



Found in Yellow- 

 stone Park and in 

 the valley of the 

 Gallatin River, 

 Montana. 



Fig. 1 1 85. Diaptomus 

 lintoni. .4 , filth feet 

 of male. X no. B, 

 terminal segments 

 of right antenna of 

 male. X 220. C, 

 fifth foot of female. 

 X2S8. (Original.) 



30 



(29) Lateral spine of second segment of right exopodite of male fifth foot 

 near the proximal end. . Diaptomus trybomi Lilljeborg 1889. 



Fig. 1 1 86. Diaptomus trybomi. .4, abdomen of female. X 70. S, fifth feet of male. X 120. 

 C, terminal segments of right antenna of male. X 100. (After De Gueme and Richard.) 



The antennal process is dentate on the outer margin and the abdomen of the female asym- 

 metrical. Has been found only in Oregon. 



Length of female, 1.5 mm. 

 Length of male, 1.4 mm. 



