606 GEOLOGICAL SUEVEY OF THE TEERITOEIES. 



HEMEROBINA. 



Polystoecliotes punctatus. 

 Micromus, spec. 

 Hemerobius, spec. 



Chrysopa, spec. 



spec. (?) 



SIALINA. 



Corydalis, spec. | Raphidia, spec. 



PHRYGANINA. 



Limnepbilus, spec. 

 Gouiotaulius, spec. 

 Stenophylax, divergens. 



Platyphylax atripes. 



designatus. 

 Eliyacopliila, spec. 



About the geographical distribution of the 36 species from 'Colorado, 

 only a few general remarks may be here given. Of the enumerated 

 species, 13 are represented by specimens in poor condition, only fit for 

 the determination of the genus, and even the whole number of 36 

 species is evidently only a small fragment of the fauna. 



There are 11 species, with a decided- alpine character, from the mount- 

 ains, Twiu Lakes," and Fair Piay, viz: Pter. hadia, Perla sobria, ehria, 

 sp. n., Eintli. semicircularis^ Polyst. 'punctahis, Semeroh. (spec.,) Limnepli, 

 (spec.,) Goniot. (spec.,) Bhyac. (spec.,) Stenoph. divergens. One of them, ■ 

 Polyst. punctatus^ occurs everywhere in the United States, the previous 

 stages probably living in the water ; Epith. semicircular is is a decided 

 alpine species, imitating the Epith. arctica from Europe, occurring in 

 Lapland and Switzerland; Stenoph. divergens is a northern species, and 

 perhaps the only one to be found also east of the Eocky Mountains. 



From the Pacific slope there are 8 species, viz : P. califortiica, Dictyopt. 

 signata, Dipl. decisa, Epith. seniicircularis, Lest. Jiamata, (Joryd. larva, 

 Bapliidia (spec). Only Lest. Jiamata lives also east of the Eocky Mount- 

 ains. The genus BapMdia is decidedly a western genus, reaching as 

 eastern liniit Colorado. EpitJiec. semicircularis goes to Vancouver's 

 Island, and perhaps more to the north. It is interesting to remark that 

 this species is imitated in the northeast by Epith. forcipata, going not 

 farther to the south than the White Mountains, New Hampshire. 



The eastern slope foot-hills, Fort Garland, and plains give 20 species; 

 only one of them, Mesoth. corrupta, is a decidedly western species, but 

 going east of the Eocky Mountains as far as the Mississippi. Some of 

 them, ^schna constricta and propinqua, seem to have their western lim- 

 its much farther than in Colorado. 



The species mentioned in my last report about the Yellowstone fauna 

 were again examined by me, and some species better determined. So 

 far as known, the fauna has a decidedly western character. From Utah, 

 Wyoming, Idaho, and Nevada there are only a few species, which do 

 not allow any general conclusions. Except some common everywhere, 

 they seem all to belong to the western fauna. 



