378 



INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



WHITE FLY PARASITE 



Pterotriw flavimedia (Howard) (Family Eulophidae) 



(Gyrolasia flavimedia Howard) 



(Fig. 378) 



Description. — This is an extremely minute parasite about 1-25 inch 

 long. The general color is rich metallic black, the second and last 



abdominal segments being 

 bright orange with bases of 

 antenna?, the legs and the 

 under side of the abdomen 

 yellow. The fore wings are 

 clear with a distinct dark spot 

 near the middle of the front 

 margin. The veins are black. 

 Distribution.— The white 

 fly parasite exists throughout 

 the State. It is specially 

 abundant at Berkeley and 

 Oakland. 



Fig. 378. — The white fly parasite, 

 flavimedia (How.). Adult, greatly 

 (After Howard, U. S. Dept. Agric.) 



Pterotrix 



enlarged. 



Host. — This species is parasitic on Aleyrodes spirceoidcs Quaint. 



THE YELLOW SCALE PARASITE 



Signiphora occidentalis Howard (Family Eulophidae) 



(Fig. 379) 



Description.— This is one of the smallest parasites, being scarcely 

 over 1-50 inch in length and rather robust. The general color is dark 

 brown or nearly black; eyes, 

 dark red; mesonotum, yellow; 

 legs and antenna?, amber; 

 wings, dusky with long fringe ; 

 forewings with indefinite dark 

 blotch near the middle. 



Distribution. — The yellow 

 scale parasite occurs in the 

 southern part of the State. It 

 does not seem to have been 

 recorded in the northern and 

 central parts. 



Host.— It is parasitic on the 

 yellow scale, Ghrysomphalus dtrinus (Coq.) 



Fig. 379. — The yellow scale parasite, Signi- 

 phora occidentalis How. Adult, greatly en- 

 larged. (After Howard, U. S. Dept. Agric.) 



