202 Sri'.FAMILY X. (TIKTLIOXIX.E. 



inent appear below the level of tlie second. Tliere is also ap- 

 parently some variation in the degree of development of the 

 sexual characters of the male. In the female the abdomen is 

 more convex, the last ventral rounded at tip or feebly concave, 

 the pygidium scarcely exposed and with short pubescence. 



The species of Bulanhius attack chestnuts, hickories, pecans, 

 hazelnuts and acorns, the adults issuing from the earth where 

 the nuts have fallen in early summer, and laying eggs in the 

 young nuts from which hatch larva* that feed on the kernel until 

 full grown. The larva? leave the nut after it has fallen to burrow 

 in the ground for a distance varying from one to ten inches, and 

 fashion there a small cell in which they pass the winter. There 

 are variations in the length of adult life, some species completing 

 their oviposition quickly and dying soon after, this being the case 

 with those attacking hazelnuts; others continuing to oviposit all 

 summer. A small percentage of the larva? may remain for more 

 than one winter in their cells; and while some species are confined 

 to a single food plant, others are less exacting. It is possible that 

 all the acorn weevils can thus accommodate themselves to a 

 change of food plant in seasons of necessity. In some sections 

 the nut weevils become of economic importance; in West Vir- 

 ginia, Brooks (1910) states that the chestnut worms spoil at 

 times 2.") to 50 per cent of the crop which in each of several coun- 

 ties is worth $3,000 or more. The pecan worm does equal injury. 

 and acorns suffer to even a greater extent; so that it is apparent 

 that the genus Jinlunlnus is capable of costing nut growers $100,- 

 000 or more annually. 



No effective remedy has been suggested; stomach poisons are 

 useless because 1 the larv.ie, feeding within the growing nuts, can- 

 not be reached; and the same is true of contact poisons. Culti- 

 vation of the soil where nut trees are planted for profit will help 

 by destroying the hibernating larvie, and trapping in bunches of 

 dry leaves hung on the trees will farther reduce the number of 

 egg-laying adults. After the nuts are gathered, fumigation with 

 bisulphide of carbon will kill those larva' that have not hatched ; 

 scalding and drying to kill such larva\ and cold storage to arrest 

 their development, have also been recommended. 



Interesting observations have been made on the natural ene- 

 mies of the nut weevils, including a bracon parasite. Urosif/al- 

 pluix (ininttnx Ashm., which deposits its egg in the orifice mad" 

 by the beetle and parasitizes 25 per cent, or less of the BaJaniunx 

 larva 1 ; several species of ants which break into the earthy cells; 

 and larva? of predaceous Coleoptera. The short-tailed shrew also 



