383 



The females become full grown early in summer, and the eggs are 

 laid during the months of May, June, and July ; these are of the usual 

 ovoid form and of a yellowish-white color. They hatch out in a few 

 weeks after being deposited, and the young larviB settle down upon the 

 under side of the leaves, arranging themselves in various positions 

 without any regard to the veins or midribs. Larviie which I found 

 September 3, on the under side of the leaves of an ash tree {Fraxinus 

 sp.), were of a paler green color than the leaf itself, being nearly con- 

 colorous with the midribs and larger veins ; they have a distinct dor- 

 sal ridge extending the entire length of the body, and with many 

 smaller ones (about 24 on each side) extending from it to the margin, 

 some of them being divided into two branches. The margin itself is 

 furnished with a row of bristle like appendages, and the ordinary four 

 lateral notches are present besides the anal cleft with its two accom- 

 panying lobes. 



At the approach of the winter season and before the leaves have 

 fallen from the trees, the larvae migrate to the twigs and smaller branches, 

 usually selecting those of the last season's growth ; here they settle down 

 invariably upon the under side of the twig or branch. A large number 

 of these larvae which I found March 4, on twigs of ash trees were of the 

 same general form as those above described, but the color is now a deep, 

 brownish red, with the legs and antennae pale yellow ; the body is now 

 nearly 1 millimetre long, evenly convex above except for the dorsal 

 ridge, twice as long as wide, and the appendages of the margin are of 

 various shapes, the greater number ot these being broadest at the mid- 

 dle. On each side of the body is a submarginal row of about five long 

 bristles, but these are easily broken off, and it is difficult to find a speci- 

 men with more than three of these bristles intact. The usual lateral 

 notches are very shallow and are usually filled up with a whitish exu- 

 dation. On April 4 I found a great many of these scales on a branch 

 of an ash tree and a majority of them were over half- grown. 



I first found specimens of this scale on apricot trees in this city; this 

 was in the summer of 1887, and at about the same time Mr. Alexander 

 Craw, of this city, also found specimens of this species, some of which 

 he forwarded to Prof. J. H. Comstock,our best authority on this group 

 of insects, and Professor Comstock replied that they evidently belonged 

 to a new species, for which he proposed the name of Lecanium pruino- 

 sum, or the "Frosted scale ;" but I am not aware that he has published 

 a description of it up to the present time. Among all the descriptions 

 of the species of Lecanium to which I have access, none agree so well 

 with the present species as does Dr. Fitch's description of his Lecanium 

 caryw (Transactions N. Y. State Agricultural Society, p. 443) ; but Pro- 

 fessor Riley, who has compared specimens of the present species with 

 Dr. Fitch's type specimen, writes me that the two species are quite dis- 

 tinct and that caryw is much larger than pruinosum. 



In Los Angeles County I have found full-grown specimens of prui- 



