348 THE UNIVERSITY SCIENCE BULLETIN. 



Form: The following are the measurements in millimeters of the 

 specimens at hand: 



Length of body 21'. 5 to 22 



Width of head 7 to 7.25 



Expanse of fore wings 60 to 65 



Greatest width of fore wing 10 to 11 



Greatest width of operculum 3 



Greatest length of operculum 4 



Length of valve 5 



The opercula are very small, widest basally, then suddenly narrowed 

 due to a sudden incurving of the lateral margin. Then they slightly 

 widen again before the lateral margin meets the mesal margin in an ob- 

 tuse point which points mesad. The valve is quite elongate and acutely 

 pointed apically. 



Genitalia; The supra-anal plate of the male is very slightly emar- 

 ginate apically. The uncus, viewed laterally, is narrow basally, then 

 widened, the margins subparallel till near the very slightly hooked apex. 

 Viewed caudally it is emarginate apically and the emargination appears 

 slightly notched on each side. The ventral piece has the arms very widely 

 separated and each is slightly notched apically. The last ventral seg- 

 ment of the male is nearly as long as wide, the lateral margins distinctly 

 sinuate and the posterior margin truncate. The pygofers of the female 

 have the posterior margins slightly sinuate on either side of the stout 

 median terminal projection. The last ventral segment of the female has 

 the lateral margins strongly narrowed and the posterior margin is 

 angularly emarginate fully one-half the distance to the base. The ovi- 

 positor is stout, the lateral pieces each bearing about a dozen broad teeth. 



Distribution: The only record of the occurrence of this 

 species in Kansas is that given by Davis who states that there 

 is a pair of specimens of this species from this state in the 

 collection of the Academy of Natural Sciences, Philadelphia. 

 Presumably it occurs in the western part of the state. The 

 specimens examined are from Colorado, Arizona, Utah and 

 Oregon. In addition Davis names the following states where 

 this species is known to occur: New Mexico, Wyoming, Mon- 

 tana, Idaho, California and Washington, and it also occurs in 

 Alberta and British Columbia. 



Remarks: As Davis mentions, members of this species have 

 in the past been confused with Okanagana rimosa (Say). 



Genus TIBICINOIDES Dist. 



The members of this genus are very like those belonging 

 to the genus Okanagana. The chief difference lies in the very 

 evident median transverse suture of the fore wings which is 

 much less distinct in the members of the latter genus. 



A single member of the genus occurs in Kansas. 



