XI Y. — The Arachnida of Colorado. 



BY NATHAN BANKS. 



Read March 25, 1895. 



During the past few ^-ears I have received several collections 

 of spiders and other arachnids from Colorado. The great pro- 

 portion of them were collected at or near Fort Collins hy Prof. 

 C. P. Gillette and Mr. C. F. Baker. Indeed, I believe their col- 

 lections are the largest that have ever been made b}' entomologists 

 in one localit}- in this country. They have also sent some from 

 other places in the State. Mr. L. M. Cockerell sent me some es- 

 pecially interesting forms from West Clifl'. 



Dr. Packard in 1875 collected some spiders in the State and 

 they were described by Thorell and Emerton. Mr. Morrison also 

 collected some arachnids and sent them to Simon ; some of these 

 have been described by Keyserling, others by Simon. Dr. Marx, 

 in his catalogue, records some other species from the State, 



Colorado presents an especially interesting arachnid fauna. To 

 receive from the same locality Lathrodectes mactans and Pa^cilo- 

 chroa monfana, Fholcus puUulus and Ergane boreoMs is not an 

 ordinar}' occurrence. There are quite a number of species which 

 are essentially northern in their distribution. Prominent among 

 these boreal forms may be mentioned the following with their 

 distribution : 



Poecilochroa montana Em. White ;Mts. ; Ithaca, N. Y. ; Colo. ; Wash. 



Drassus robustus Em. N. H. ; N. Y. ; Colo. ; W^ash. ; Cau. 



Gnaplu>sa conspersa Thor. N. H. ; Ithaca, N. Y. ; Colo. ; Wash. ; Cau. 



Gnaphosa brumalis Thor. N. H. ; Ithaca, N. Y. ; Colo. ; Cau. 



Crustulina sticta Cauibr. N. H. ; INIich. ; Colo. 



3Iicroneta 5-dentata Em. N. H. ; Ithaca, X. Y. ; Colo. 



Epeira carbonaria Koch. Labrador; Mt. Washiugtou; Loug's Peak. 



Epeira patagiata Clerk. N. H. ; N. Y. ; Mich. ; Colo. ; Wash. ; Cau. 



Lari Ilia boreal is Hks. N. H. ; Colo.; Wash. 



Symema obscum Keys. Mt. Washiugtou; Colo. 



Pardom grcenlandica Thor. Labrador ; White Jits. ; Eocky Mts. 



