THE COLEOPTERA 135 



in the high mountains to hibernate and while thus collected in quantities 

 they are gathered and in spring distiibuted through the truck-growing 

 regions to attack the plant lice, about 30,000 being regarded as enough to 

 protect the plants growing on 10 acres. Several tons are often collected 

 for distribution for this purpose. It takes nearly 1,500 of these beetles 

 to weigh an ounce. 



Because of their efficiency as feeders on insect pests, a number of kinds 

 have been introduced into this country to attack the special insects of 

 their native lands which have reached the United States and have become 

 pests here. Among these are the Vedalia (Novius cardinalis Muls.) 

 (See Fig. 216), imported from Australia to attack the Cottony-cushion or 

 Fluted Scale; the Mealy-bug Destroyer (Cryptolcemus montrouzieri Muls.), 

 brought also from Australia to attack several kinds of Mealy-bugs found 

 in California; the Steel-blue Lady beetle (Orcus chalybeus Boisd.) which 

 feeds on a number of kinds of Armored Scales ; and the Black Lady beetle 

 (Rhizobius ventralis Erichs.) which is an active enemy of the Black Scale 

 (Saissetia olece Bern.) ; besides numerous other species. Many of these 

 imported forms have done valiant work in their attacks upon their 

 ancient foes in the country to which both have come, but in some cases 

 this attempt to aid nature in the control of insect pests has been less 

 successful, and it is evident that the success of each experiment of this 

 kind can rarely be determined beforehand. (See Cottony Cushion Scale, 

 Chapter XXVI). 



Family Tenebrionidae (Darkling Beetles). This rather large family of beetles 

 contains many forms found on the ground and superficially resembling the Cara- 

 bidse. They are usually rather slow of movement, however, feed on vegetable 

 instead of animal food, and while their fore and middle _____ _ , 



tarsi are each composed of five segments as in the Carabids, 

 their hind tarsi each have only four. They are particularly 

 abundant in the Southwest and West, though a number 

 are present practically everywhere. 



The Yellow Meal-Worm (Tenebrio molitor L.) about 

 three-quarters of an inch long (Fig. 127), is often found 

 around stores of grain, in pantries, stables etc., and its larva 

 which closely resembles a wireworm, feeds upon meal and 

 similar materials. It is often raised as food for cage birds. 

 Where abundant, a thorough cleaning out of infested places, 



followed by sprinkling air-slaked lime around, or fumigation molitor L.), about 



of the infested material with Carbon disulfid, is all that is natural size. (Orig- 



inal.) 

 necessary. 



Family Meloidae (Blister Beetles). The insects of this family also 

 have but four segments to each hind tarsus. The body is quite cylin- 

 drical and rather soft, and the head joins the thorax by a distinct neck 

 (Fig. 128). Many of the members of this family contain a substance 



