238 THE MONTHLY BULLETIN. 



THE PEA WEEVIL. 



*Laria pisorum (Liun.) (Family Bruchidse). 



{Bruchus ■pisorum Linn.) 



(Fig. 235.) 



General Appearance. — The adult beetles are about three eighths of 

 an inch long, brownish black in color with well defined light spots on 

 the wing covers and a distinct white spot on the hinder part of the 

 thorax near the base of the wing covers. The eggs are very small 

 (1.5 mm. long) and deep yellow in color. The larva3 are yellowish in 

 color with a dark head. The pupse are first light, gradually becom- 

 ing darker with age. 



Life History. — The adult hibernating weevils appear in the spring 

 and as soon as the pods are formed on the vines begin egg-laying. 

 The eggs are thrust inside of the pod by the females, thus being 

 thoroughly protected and out of sight. The young grubs, as soon as 

 hatched, bore into the tender peas and remain inside, drilling out 



CL 



Fig. 235. — The pea weevil, Laria pisorum (Linn.), a, adult 

 beetle; b, larva; e, pupa. (After Chittenden.) 



sufficient room until they are ready to emerge as adults in the fall. 

 This is accomplished by cutting a circular hole in one side of the pea. 

 Unlike the bean weevil, this species works only upon the peas origi- 

 nall.y attacked when green and does not continue to breed upon dried 

 and stored seed. There is but one uneven brood a year. 



Distribution. — Common throughout the State, but not troublesome 

 in all the pea-growing sections. 



Foods. — "Works upon all varieties of garden and flower peas. 



Control. — As the seed is infested before harvesting, control measures 

 are of little avail, except to prevent a reinfestation b}'- means of the 

 seed. A thorough fumigation with carbon bisulfid is a sure way of 

 accomplishing this. 



*NoTE. — The pea weevil greatly resembles the broad-bean weevil, Laria rufimana 

 Boh. The principal differences are given by F. H. Chittenden in the following 

 tabular form : 



Posterior femora acutely dentate ; thorax broad ; pattern of elytra well 

 defined ; pygidium with a pair of distinct apical black spots pisorum L. 



Posterior femora obtusely or obsoletely dentate ; thorax narrow ; pattern 

 of elytra more or less suffused ; pygidium with black apical spots lacking 

 or illy defined rufimana Boh. 



