THE INSECT DESCRIBED. 



The mature Sau Jose scale is small, *i;rayisli in color, circular in 

 outline, somewhat convex, and w itli a nipplelike prominence in the 

 center. The female scale is about 1 millimeter in diameter (about the 

 size of a pin head) ; the male scale is nuich smaller and elongate. (See 

 fig. 3.) The insect itself is beneath the so-called scale, this being 

 sim[)ly a waxy covering secreted by the soft, helpless, yellow "louse" 

 for its own protection. "V^Tiere trees and plants are but slightly 

 infested its presence is not readily detected by the casual observer, 

 but in the case of severe infestation the bark of the tree and limbs 



Fig. 2.— Appearance of an apple oruharU badly infested by the San Jose scale; many of the liinlis and 



Itranches killed. fOrii,'inal.) 



will present an ash-gray aj)j)earance, and on closer examination will 

 be found thoroughly incrusted with the scales, which, when scraped 

 with a knife, will produce a yellowish, oily fluid. Wlien the scales 

 are abundant on the tree the foliage also will be thoroughly infested, 

 giving it a spotted and diseased aj)pearance readily o])s(>rval)le some 

 feet away. 



NATURAL HISTORY AND HABITS. 



The San Jose scale passes the winter in an inunature condition 

 fixed to the bark of the host })lant, the small, dark-gra}^ or bbu-kisli 

 scales being just discernible with the unaided eye. In early sj)ring, 



[Cir. llM] 



