2B4 IlJ'nioh State Ijahoratorn of Ndtiind H'tHtorii. 



lamella on the upper spine of this margin, and the small 

 spine on the apex of the segment are all omitted. In the 

 figures of the fifth pair of legs of the male, the small spines 

 at the outer apical angles of the segments of both outer rami, 

 the spine at the inner apical angle of the last segment of the 

 right outer ramus, and the hairs on the inner margin of the 

 first segment of both inner rami are wantiug. 



Although this species is widely distributed, — haviug l)een 

 found in Alabama, Illinois, Minnesota, Oregon, and Wyo- 

 ming, — no differences sufficient to establish even a new 

 variety have been found in specimens from these localities 

 so widely separated and so varied in character. Herrick, in 

 his papers, states that all the specimens examined by him, 

 from Alabama to JNIinnesota, had '24-segmeuted antenn:e. 

 Forbes found the antenna' '23-segmented, de Guerue and 

 Piichard, who examined specimens sent to Poppe ])y Forbes, 

 agreed with him, and the writer also found the antenna^ of all 

 the specimens he examined to be '28-segmented. The speci- 

 mens collected by Dr. Forbes in April, 1877, and described in 

 1882, were uniform pale brown; those collected l)y the 

 W'riter at Havana, 111., in July, 1896, were hyaline or ojial- 

 escent white; while a single male found in June, 1897, at 

 I'rbana, 111., in a temporary pool, was bright scarlet through- 

 out, and hardly to be distinguished from the specimens of 

 1). sdiujii'niciix among which it was found. Herrick has found 

 OapJirnntJcuiii in "estuaries of running water," and says that 

 according to his observations it prefers such localities. The 

 writer's observations tend to conffrm Forbes's statement 

 that it prefers swamps and pools, or at least quiet or stag- 

 nant water. At the Biological Station at Havana, during 

 the summer of 1896, a single specimen was captured in the 

 Illinois Eiver, in midstream, Avhile in Quiver Lake, in a mat 

 formed of CcrdtojihiiUinii and Lfiiiint in a stagnant i)ortion 

 near shore (substation C), they were comparatively numer- 

 ous, though not occurring in any such numbers as either 

 l)hi})t()ini(H or (Uiclopx. In fact, in noiie of the collections 

 examined were they at all common. 



Prof. Forbes, in connection with the original description, 



