CHARLES W. HOOKER. 147 



ate ; abdomen fulvo-ferruginous, sometimes almost fuscous, strongly 

 compressed. 



Redescribed from type and numerous specimens of both 

 sexes. 



Type — 9 . No. 3296, U. S. National Museum. 



The questionable stability and reasons for restricting the 

 species are discussed under E. macrurus L. The existence 

 of light specimens of macrurus with hyaline wings has led to 

 considerable confusion. A large series of specimens shows 

 at once that macrtirus is quite variable in such characters as 

 color, venation and size. The hyaline wings and arcuate 

 shape of the discocubital vein in arctics seem to be well fixed, 

 and for this reason I have retained the species, drawing the 

 limits closer. Breeding experiments may perhaps show that 

 arctice is only a subspecies of 7nacrurus. 



Distribution. — This species ranges through southern Can- 

 ada, the United States and northern Mexico, from Ottawa, 

 Canada, and Amherst, Mass., to Georgia, Mississippi and 

 California. It appears to have a more limited range than 

 E. macrurus, being more restricted to the southern United 

 States. Owing to confusion with the latter, and the present 

 narrowing of the species, many of the records are uncertain, 

 but it has been reported from the following places : Ottawa, 

 Can.; Amherst, Mass.; Vineland, N. J.; Pennsylvania; 

 Washington, D. C. ; Tennessee ; Jackson, S. C. ; Mississippi ; 

 Selma, Ala. ; Santa Cruz Mountains and Alam.eda County, 

 Cal. I have seen specimens from the following locations : 

 Harrisburg, Pa. ; Tennessee ; Tifton, Ga. ; Thomasville, 

 Ala., February 12, and Dallas, Tex., April 8; Baldwin and 

 Onaga, Kans. ; Indiana ; Los Angeles and Stanford Univer- 

 sity, Cal. 



Life history and habits. — Little is recorded of the life his- 

 tory of this species, but so far as known it agrees with that 

 of E. macrurus. It preys for the most part on some of the 

 arctians, though it has been reared from saturnians. The 

 cocoon of one specimen from California shows that the para- 

 site spun up and pupated within the body of its host, Halisi- ♦ 

 dota agassizii, but this habit is probably variable. In this 



TRANS. AM. ENT. SOC, XXX VIII. 



