THE GENUS DENDROCTONUS. 



137 



7.5 mm. in length, with the head broad and convex; the prothorax 

 slightly narrower than elytra, its sides narrowed and slightly con- 

 stricted toward the head, the surface even and shining, with coarse 

 and small punctures intermixed; the elytra with moderately coarse 

 rugosities between rows of moderately coarse and but slightly im- 

 pressed rows of punctures, and the declivity smooth and shining in 

 the female and less shining and more rugose in the male. It attacks 

 felled white pine in northwestern Michigan. The primary or egg 

 gallery is evidently of the same character as those of the spruce 

 beetles, but the larval mines are probably like those of the European 

 spruce beetle and the black and red turpentine beetles of this coun- 

 try. The larvae resemble those of the eastern spruce beetle in the 



Fig. 88.— The redwinged pine beetle: Distribution map. (Author's illustration.) 



dorsal plates on the last two abdominal segments, but are distin- 

 guished by a row of brown spots (spiracles) on each side of the body, 

 as in figure 87, B. 



SEASONAL HISTORY. 



This species evidently passes the winter in the adult and larval 

 stages. Fully developed broods and larvse were found by Mr. W. F. 

 Fiske, October 20, at Grand Island, Mich. Nothing further is 

 known of the life history, but it is probable that it will not differ 

 materially from that of the eastern spruce beetle. 



HABITS. 



Mr. Fiske found the developed broods under the bark on the 

 underside of the trunk of a storm-felled white pine some distance 

 from the base. Nothing further is known of the habits of this 



