210 Marsh — Cydopidce and Calanidce of Wisconsin. 



mens have several, agreeing in tins respect with the figure of 

 Hoek. 



It occurs in both day and evening collections, and is gener- 

 ally reddish in color. 



This is one of the most widely distributed of all the species 

 of Cyclops, being found in various parts of Europe, in Asia, 

 Africa, Madagascar, Ceylon, and the East Indies (34:). Herrick 

 mentions it as occurring in Alabama (30), and it is probable 

 that it is widely distributed in America. It seems to me prob- 

 able that the species identified by Herrick as oithonoides (26, 

 p. 150, pi. S, figs. 2-6), is really leuckarti. 



Brady's scourfeldi corresponds to this species in all details 

 except the armature of the terminal joint of the outer branch 

 of the fourth foot. The special character by which he distin- 

 guishes the species, — the marginal setae uf the second maxilli- 

 pedes, — I find in my specimens. In his figure of the fourth 

 foot, the terminal joint of the outer branch has one spine and 

 two setce on the apex, instead of the normal armature of one 

 spine and one seta. Schmeil's figure of the fourth foot (41, pi. 

 Ill, fig. 6) shows an armature like that of the American speci- 

 mens, and one cannot help thinking that Brady's figure must 

 have been drawn from an abnormal specimen. 



C. edax Forbes appears to differ from leuckarti only in that it 

 lacks the ridge on the terminal joint of the antennae, and is 

 probably simply a less highly developed variety of the same 

 species. 



There is considerable variation in the form of the spines of 

 the swimming feet; in some specimens they are very slender and: 

 the joints are at the same time somewhat elongated, while in 

 other cases they are robust. The robust form appears to be 

 characteristic of the littoral specimens, and the slender form of 

 the pelagic. 



The armature of the terminal joints of the swimming feet is 

 as follows : 



FIRST FOOT. 



Outer br. ex. 2 spines. Inner br. ex. 1 seta. 



ap. 2 setae. ap. 1 spine, 1 seta, 



in. 2 setae. in. 3 setae. 



