80 THE CANADIAN ENTOMOLOGIST. 



THE STONEFLIES OF THE GENUS PELTOPERLA.'g 



liY JAMES G. NEEDHAM AND LUCY W. SMITH, ITHACA, N. Y. 



This obscure genus of stone-flies is of wide distribution in 

 North America, and it inchidcs a considerable numl;er of species, 

 only two of which ha^•e hitherto l)een made known. The type 

 species P arcuata was descril^ed by the senior author in 1809 in 

 the Proceedings of the Biological Society of ]] asliin;.'Jou. However, 

 specimens of both adult and lar\a of this species had long reposed 

 in the Cornell University collection. In 1907 Nathan Banks 

 described a second species, P. minor, from British Columbia. In 

 1912, Professor H. Garman published an excellent figure of a nymph 

 belonging in this genus in Bulletin No. 159 of the Kentucky Agiicul- 

 turai Experiment Station. This specimen was from a rill flowing into 

 Straight Creek near Cary, Kentuck\', and was labelled "An Un- 

 determined Stonefly nymph, (Xo. 3)." 



Meanwhile specimens for study have been coming intcj our 

 hands from various quarters: from Ramapo, N. Y., contributed 

 by Mr William T. Davis; from Black Mts , N. Carolina, loaned 

 b\ Mr. William Beutenmuller; from several localities in Georgia, 

 collected by Dr. J. C. Bradle>'; from Nevada, loaned from the 

 Museum of Comparative Zoology by the curator. Mr. Samuel 

 Henshaw. There arc also a few specimens bearing only general 

 locality designation from unknown sources in the Cornell Uni- 

 \ersity collections, and along with these a few nymphs from 

 British Columbia, from California, from Arizona,. and from Wash- 

 ington, D. C. One species, described below^ as P. maria, from 

 Pelham, Mass., has been collected and reared by the junior author. 

 No good characters have as yet been discovered for distinguishing 

 this n\-mph from that of P. arcuata, or from those of the other 

 species which have not as yet been reared. This paper w ill there- 

 fore be limited to characterization of the adult forms. 



Soft-bodied stoneflies such as these make very unsatisfactory 

 pinned specimens. They shrivel like prunes in drying, and, as a 

 rule, the best difl'erential characters offered by the genitalia may 

 be made out only by boiling and softening and expanding the 

 specimens The colours fade hopelessly, either pinned or in alcohol. 

 Our descriptions of colour will 'therefore be useful only in so far 



March. 1916 



