INSECTS INFESTING THE PEAR TREE. 113 



I received the following, dated — 



" Ithaca, N. Y., March 3, 1882. 

 "Your letter and specimens duly received. Without doubt 

 you are right. The scale is Diaspis ostrexformU. This is very 

 important, as it is the first instance of which I know of this 

 species in this country. Strong measures should be taken to 

 crush it out before it gains a foothold," etc. 



"J. H. COMSTOCK." 



This species is found on pear and apple trees in the vicinity 

 of Sacramento ; it is not known what length of time the trees 

 have been infested, but serious damage has been done. In 

 many cases the bark is destroyed. 



NATURAL^ HISTORY. 



The scale of the female insect is nearly circular, or a broad 

 oval, and measures about three fourths of a line in diameter — 

 color, ashy-gray ; exuviae in the center, or nearly so, yellow- 

 ish-brown ; the inside of the scale and the venter is snowy 

 white. ^ 



The scale of the male is elongated. The eggs are pinkish- 

 red and ovate. The female insect is of a reddish-purple color, 

 and in form is somewhat elongated. There are at least two 

 broods each year, as I have found the eggs early in May, and 

 also in the latter part of July. The male insect is winged, 

 and is described by Curtis as being of a bright ochreous 

 color, with a black band on the thorax. 



Remedies. — When the tree is dormant, a thorough spraying 

 with No. 13 — one pound of mixture to each gallon of water used. 

 Summer wash, Nos. 5 or 7. Where trees are seriously infested, 

 when dormant No. 44 may be used as a spray, but followed 

 by No. 13 in about twenty-four hours. 



