1914.] NATURAL SCIENCES OF PHILADELPHIA. 115 



of Mesilla material as belonging to two species is due to a compilation 

 of determinations made at different times, one before the recognition 

 of brevihastata, and that both records relate to the same species. 



The species D. Icevis, erected by the senior author on a single 

 female, is a sjTionym of the present species. The peculiarities of the 

 ovipositor of the type of Icevis, the unarmed margins of which sug- 

 gested the specific name, we now know are due to the immaturity 

 of the individual. The latter is in the stage immediately preceding 

 maturity and its proper relationship to the other material now in 

 hand is very evident. The more robust character of the limbs and 

 smaller size of the type of Iwvis are similarly explained. 



Remarks. — -The variation in the length of the pronotum as found 

 in certain females has been touched upon above under the measure- 

 ments, this being the most decided fluctuation from the more general 

 tjT)e found in the species. After considerable study and considera- 

 tion from different view points, we have concluded that this phase 

 cannot be separated from the more typical one of brevihastata, that 

 it is a fluctuation occurring anywhere in the range of the species, 

 although more numerous in certain regions than in others, and is 

 approached by a few specimens not typical of the same and again 

 not exactly similar to the type of brevihastata. There is, of course, 

 a possibility that future work may show the advisability of recognizing 

 the larger pronotum type as distinct, but we do not feel that the 

 necessary evidence will be forthcoming. 



Speciviens Examined. — 103; 47 males, 46 females, 4 male nymphs, 

 6 female nymphs. 



Sycamore Canyon, Baboquivari Mts., Pima Co., Arizona, elev. 

 3,700-4,700 feet, October 6-9, 1910, (R. and H.), 2 cf , 3 9 . 



Tumamoc Hill, Tucson Mts., Pima Co., Arizona, elev. 2,400-3,092 

 feet, October 3-4, 1910, (R. and H.), 3 cf , 3 9 . 



Carr Canyon, Huachuca Mts., Cochise Co., Arizona, August, 1905, 

 (H. Skinner), 1 a', 1 9 nymph. Type ( 9 n.) of D. Icevis, [A. N. S. P.]. 



Riley's Ranch, Mesiilla Valley, New Mexico, August 16, (Cockerell), 



1 c^. Type, [Scudder Coll.]. 



Mesilla Park, New Mexico, August 7 and September 11, (Cock- 

 erell), 2 9 . Allotype and paratype, [Scudder Coll.]. 



Dry Canyon, Sacramento Mts., Otero Co., New Mexico, elev. 

 4,800 feet, July 13, 1907, (R. and H.), 1 9 nymph. 



Marathon, Brewster Co., Texas, elev. 3,900-4,160 feet, August 

 26-27 and September 12-13, lj)12, (R. and H.), 16 c^, 14 9 , 2 o" and 



2 9 nymphs. 



