THE COCCIDAE OF CALIFORNIA. 



13 



Subfamily MONOPHLEBINjE. 



Icerya purchasi crawii Ckll. 



Female (after forming ovisac). Light pinkish or yellowish red; the 

 margin orange, with bunches of short black bristles; the back is largely 

 covered with yellowish-white secretion. Ovisac somewhat larger and 

 longer than mcutkclli', femora decidedly more slender. 



On orange, lemon, grape-fruit, acacia, pittosporum, broom, rose. 



X 



FIG. 1. Icerya purchasi crawii. Females on orange twig. 



FIG. 2. Male of 

 Icerya purchasi 

 crawii. 



Icerya purchasi maskelli Ckll. 



Female (after forming ovisac). Slate gray or very dark purplish 

 gray, sometimes brownish in the middle, with marginal dull orange 

 spots. Back little covered by secretion. More hairy at the cephalic 

 end than crawii. Ovisac not so large as in crawii, tinged with yellow 

 just behind the body of the insect. It is purchasi in the strict sense and 

 agrees very nearly, though not entirely, with Maskell's description. 



Food plants: same as I. crawii. 



FIG. 3. Icerya purchasi maskelli. Females on orange twig. 



The two species above mentioned are well known to almost every resi- 

 dent of California, and are commonly known as the cottony-cushion 

 scale, the white scale, or the fluted scale. Until the introduction of 

 their natural insect enemy (Novius [ Vedalia] cardinalis) this pest 

 engaged the attention of our citrus-growers more than any one thing, 

 but within a few short months after its introduction, N. cardinalis had 

 the pest practically controlled and has held it so for many years. To- 

 day it is hard work to find enough of the scale to keep the breeding 

 cases in our Insectary supplied with food. The two species mentioned 

 are usually associated with each other on the same tree. They may be 

 distinguished in the adult stage, however, as one is a light form and 

 the other dark. 



