THE MONTHLY BULLETIN. 



225 



Hosts. — The larvas and adults of this beetle are voracious feeders 

 upon red scale {Chrysomphalus aurantii), yellow scale {Chrysomphalus 

 citrinus), ivy scale {Aspidiotus hederce), pernicious scale {Aspidiotus 

 perniciosiis) , purple scale {Lepidosaphes heckii), the citrus mealy bug 

 (Pseudococcus ciiri) and black scale {Saissetia olece). 



THE CALIFORNIA GRAPE ROOT-WORM. 



*Adoxus ohscurus Linn. (Family Chrysomelidae). 

 (Figs. 224, 225.) 



General Appearance. — The adult beetles are about three sixteenths 

 of an inch long, jet black in color and partially covered with fine 

 whitish hairs giving them a grayish cast. The prothorax is noticeably 

 narrower than the rest of the body. The antennjB and legs are usually 

 black, but are sometimes brown. The eggs are elongated, yellowish- 

 white and one twenty-fifth of an inch long. The full-grown larvas are 

 white with brown heads and about one fourth of an inch long. The 

 heads are usually curved in towards the ventral surface of the body. 

 The pup* are white and about the same size as the fully developed 

 larvae. 



Fig. 224. — Work of the California grape root- 

 worm iAdoxus obscurus Linn.) on leaf. (Cal. Hort. 

 Com.) 



Life History.— The eggs are laid early in the spring, usually in 

 clusters of from one to two dozen in cracks or crevices beneath the bark 

 upon the trunk of the vines, anywhere within six inches above the 

 surface of the ground. They hatch in from eight to ten days and the 

 young larv£e immediately seek the roots of the vines underneath the 

 ground and attack first the small rootlets which are often entirely 



*Tlie light-colored form has the wing covers, tibiae and basal half of the antennae 

 brown, while the rest of the body is black. This species is known as Adoxus vitis 

 Fourc, and the life history and habits are almost identical with those of Adoxus 

 oiscurus Linn. 

 11— H 



