PSYCHE. 



LIFE HISTORY OF CLISIOCAMPA PLUVIALIS DYAR. 



BY HAKRISdN G. DYAR. 

 C. PLUVIALIS DyAR. 



1SS3 — Stretch, P.ipilio, iii, 20 (as larva 



no. I ). 

 1893 — Dyar, Can. entom., xxv, 43. 



I have been enabled to complete the 

 lite history of this species through 

 the kindness of Prof. O. B. Johnson of 

 Seattle, and Prof. C. V. Piper of Pull- 

 man, Washington. 



Both of these gentlemen have 

 sent me eggs and examples of 

 the moth. 



C. pliivialis occurs through- 

 out the Pacitic Northwest where 

 it represents fragilis. I have 

 found the nests at Victoria, 

 B. C. on Vancouver Island, at 

 Tacoma and .Seattle in Wash- 

 ington, and Portland, Oregon. 

 It is recorded from Astoria, 

 Oregon by Mr. R. H. Stretch, 

 and sent me by Mr. Piper fi'om 

 Pullman, Washington. 



The fully marked larvae look .strik- 

 ingly different from fragilis., yet the 

 two are exactly alike in pattern, and 

 whereas in pl/ivialis the orange marks 

 are greatly developed and the blue 

 reduced, in fragilis the orange is 

 reduced almost to oljliteration and the 

 blue greatly extended. Mr, Stretch 

 has noted a considerable rancje of varia- 



^L, NEW YORK. 



tion in the Astoria larvae. He says 

 that thev varied by the expansion or 

 contraction of the dorsal orange mark- 

 ings, and in the latter case the blue 

 became strikingly visible. This is a 

 greatei' range of variation than I have 

 happened to oliserve in any one locality, 

 but the specimens sent me by Mr. Piper 

 have the orange considerabI\- reduced. 



Segments of stage i, X ^5. 



I suspect that as we go East the orange 

 maiks will tend to be supplanted by 

 the blue, and this species will grade 

 xnto fragilis. However, I have vet to 

 see larvae which are not definitely one 

 or the other, and the moths seem not to 

 pass into each other, though the Idaho 

 region is still to be explored. 



