Occasional Papers of the Museum of Zoology 25 



iliis species, and bears considerable resemblance to the form 

 with the light pronotum ; in the southwest S. collai'e is quite 

 often found with S. aeqtiale^ though it seems to prefer less 

 barren habitats than that species. 



A series of 60 specimens, representing all of the above local- 

 ities, was sent for determination to Dr. A. P. Morse. All but 

 three of these specimens were determined by him as Spharage- 

 inon collare ( Scudder) ; the remaining three specimens, two 

 males from Devils Lake and one male from Bottineau, were 

 named Spliaragcuwn collare wyomingianum (Thomas). A 

 series of 35 specimens sent to Mr. J. A. G. Rehn was deter- 

 mined by him as Spharagemon collare collare (Scudder). On 

 examining the entire series of 167 specimens I was unable to 

 separate them into racial groups, although great differences 

 of size and amount of development of the pronotal crest are 

 evident. A number of the males from the eastern part of the 

 state are similar to Michigan specimens of S- c. wyomingianum 

 determined by Rehn and Morse, but the females seem too 

 robust for that race, with more rounded head and less prom- 

 inent eyes. This eastern material may represent a transitional 

 group of the species with average intermediate characters, 

 although there is great individual variation shown. The west- 

 ern material is much less variable, all of the specimens being 

 typical collare, and averaging- larger than the eastern material, 

 though a number of the females from the eastern part of the 

 state are fully as large as any of the western specimens. 



Derotmcma haydenii haydenii (Thomas). — Buford, July 23, 

 1920, I male; Medora, July 29, 1920, i male, i female; iVmi- 

 don, Aug. 23, 1920, II males, 14 females. 



At Buford and Medora this species was taken among sparse 

 vegetation on arid hillsides. At Amidon a rather numerous 

 colony was discovered on the dry, sparsely vegetated margins 



