58 COOK 



can genera. The much rounded carinae suggest those of Hybaphe 

 curtipes, but the gonapods are so unlike as to forbid the inference of 

 close relationship. Females have the carinas still further reduced. 



ISAPHE CONVEXA sp. nov. 



(pi. IV, figs, la, 16.) 



Type. No. 788, U. S. Nat. Mus. Collected by John B. Leiberg 

 in Kootenai County, Idaho, August, 1890. 



Length of male about 30 mm. ; width 5.3 mm. ; length of antenna 

 4.3 mm. ; of leg 4 mm. 



Color in alcohol brown, darkest across the middle of the segment ; 

 carinae yellowish, also a transverse band occupying the middle third of 

 the posterior margin of each segment. The lighter area is larger and 

 less distinctly defined on posterior segments. 



Surface of segments smooth and shining. 



Gonapods with extremely long bristles arising from the basal por- 

 tion of the second joint. The prongs are of nearly equal length, the 

 anterior being somewhat more slender, and having a double curve 

 near the base, while the other is simply arcuate. 



A male and two female specimens were collected by Mr. Leiberg. 



Hybaphe gen. nov. 



Type. Hybaphe tersa, from State of Washington. 



Related to Isaphe and to Harpaphe; from the former it differs in 

 the less convex dorsum and in the very small and spine-like anterior 

 ramus of the gonapod. The posterior branch is much longer and is 

 much more curved than in Isaphe. 



From Harpaphe the present genus is distinct in the strongly 

 rounded posterior corners of the carinas, and in the long, strongly 

 decurved, subterete gonapods. 



HYBAPHE TERSA sp. nov. 

 (pi. iv, fig. 3<z.) 



Type. No. 789, U. S. Nat. Mus. Collected by C. V. Piper at 

 Almota, Washington. 



Length of male 37 mm. ; width 6 mm. ; length of antenna 5.3 mm. ; 

 length of leg from middle of body 5.5 mm., with claw 6 mm. 



Color of alcoholic specimen dark grayish-brown ; carinse yellowish ; 

 legs very dull reddish ; antennae much darker reddish, except at the 

 yellowish articulations. 



