200 Marsh — Cyclopidoe and Calanidw of Wisconsin. 



It is probable, as stated by DeGuerne and Richard, that it is a 

 common species through the northern part of North America. 

 It is common in the pelagic collections from Green Lake, but 

 I have found it nowhere else in central Wisconsin; it is possi- 

 ble that this is near the southern limit of the species. The 

 stout terminal claw of the outer ramus of the right fifth foot 

 in the male, and the short, leaf-like inner rami of the fifth foot 

 of the female, make this species one easily recognized. 



Diaptomus oregonensis Lilljeborg. 



Plate IV. Figs. 4 and 5. 



1889. D. oregonensis DeG-uerne and Richard (Lillj.) (32) p. 53, 

 pi. II, fig. 5, pi. Ill, fig. 8. 



This is the most common species of diaptomus, being found 

 quite generally in the shallower lakes. It is easily distin- 

 guished from the other species by the form of the male fifth 

 foot. 



The type specimens were obtained from Portland, Oregon, 

 and according to the figures in DeGuerne and Richard's "Re- 

 vision" are somewhat more slender in all their parts than are 

 my specimens. 



Genus EPISCHURA Forbes. 

 Epischura lacustris Forbes. 

 Plate IV. Fig. 6. 



1882. E. lacustris Forbes (22) pp. 541 and 648, pi. VIII, 



figs. 15, 16, 21, 23, pi. IX, fig. 8. 

 1884. E. lacustris Herrick (26) p. 131, pi. Q, fig. 13. 

 1889. " « DeGuerne and Richard (32) p. 90, pi. IV, 



figs. 3, 9 and 10. 

 1891. E. lacustris Forbes (35) p. 704, pi. I, figs. 1-5, pi. II, 



fig. 7. 



