ORDER COLEOPTERA 205 



left exposed and uneaten soon turns black and an old mine 

 is all black except for the small marginal lobe in which a 

 larva is still at work. 



The larvae are essentially solitary, except when two or 

 more mines on a single leaf become confluent and then they 

 feed widely apart. Usually only a single living larva is 

 found in even the large compound mines when completed, 

 the several dead ones are often present. 



When grown the larvae break through the loosened epi- 

 dermis and fall to the ground and bury themselves there 

 before transforming to pupae. They enter upon hiberna- 

 tion curled up in a little oval earthen cell hollowed out in 

 the soil several inches beneath the surface. 



The adults are black and yellow, oblong beetles, about 

 an eighth of an inch long, with coarsely punctate elytra. 

 There is a prominent tubercle on either side of the prothorax, 

 the elytra and abdomen are black and the remainder of the 

 body is yellow. 



FAMILY CURCULIONIDAE 



It has long been known that the larvae of a few of the 

 snout beetles live in tunnels in the interior of leaves and then 

 pupate in the mines either free or in silken cocoons. 

 Frisch, 1721, Reamur in 1737 and Swammerdam in 1758 all 

 give accounts of weevil miners. Reamur figures the larva 

 of one. All these undoubtedly refer to members of the 

 genus Orchestes, to which genus most of the weevil miners 

 belong. 



Of this, the largest family in the world, only a few mem- 

 bers are leaf-miners and these few are not very different as 

 larvae from their stem-boring allies, only a little more 

 flattened, and less arcuate in form. The larvae are legless. 

 The pro thoracic dorsum is chitinized only at the front. 

 The body is widest across the base of the abdomen and 

 there are deep incisures between the abdominal segments 



