390 Illinois State Laboratory of Natural History. 



Types in collections of the Illinois State Laboratory of 

 Natural History and of the United States National 

 Museum, and in the author's collection. 



I have found this species on one tree only, and in 

 very limited numbers. So far as I have observed it 

 does not attack the branches, twigs, or leaves, but 

 lives exclusively upon the new bark of the trunk, cluster- 

 ing between the cracks in the old bark. It often gathers 

 in great numbers, and the masses of scales resemble 

 small shells. I have not worked out its life history as 

 to the number of broods, since it is of little consequence 

 from the economical standpoint. 



I have bred from this insect two species of hymenop- 

 terous parasites, Prospalta murtfeldti How., and Coccoph- 

 agus fraternus How. 



Chionaspis Sigxoret. 



Chionaspis americana sp. n. (Plates XXXIII. and 

 • XXXIV. 



Scale of female. — The scale of the female is fawn-color 

 at first, but becomes more or less bleached during the 

 fall and winter months, presenting a dirty whitish ap- 

 pearance in the spring. The first larval skin is yellowish, 

 the second is claret-brown, approaching a maroon, and is 

 covered with slight secretion. The interior lining of the 

 scale is snowy white, and when removed from the twig- 

 it leaves a whitish- scar, the margins of which are very 

 distinct. In general outline the scale resembles that of 

 Chionaspis furfurus, but is more convex. It widens near 

 the posterior end of the second larval skin, some scales 

 bending abruptly to the right or left, and others being 

 straight. Length 2-3 mm.; width 1.5-2 mm. 



Scale of male. — The scale of the male is snowy white, 

 straight, tricarinate, about .73 mm. long, and .30 mm. 

 wide; the sides rough and nearly parallel; larval skin 

 vellowish. 



