ORDER COLEOPTERA 199 



the mine. In from two to four days, after having eaten 

 half or more of the first leaf they leave the mine and wander 

 to other leaves and separately make new mines, each on a 

 leaf and in a mine of its own. There are several such 

 changes of habitation, and the damage to the tree is greatly 

 increased by this uneconomical habit. The larval life 

 appears to last about 3 weeks. 



The larva is rather unspecialized for a leaf-miner. It is 

 only a little depressed and not much narrowed behind the 

 pro thorax. The second and third segments of the thorax 

 are distinctly wider than the first. Legs are well developed. 

 The body is yellowish- white, with darker chitinization of 

 head, prothoracic disc, legs and dorsum of anal segment. 

 The abdominal segments are triangularly produced at the 

 sides each into the thin, flat, spine-tipped tooth. 



Pupation occurs within the mine and the pupal stage lasts 

 a week or ten days. The adult beetle, emerging breaks its 

 way out through the thin and brittle epidermis of the leaf. 

 There is apparently a single brood annually northward with 

 more than one in the South. The adult beetles hibernate. 



Several other species of Chalepini are known in North 

 America. Those of which the life histories have been 

 worked out are all leaf-miners. The best known, Baliosus 

 ruber, attacks the leaves of several trees including white 

 oak and apple, but its favorite food plant seems to be 

 the linden. It, too, hibernates as an adult and begins 

 depositing eggs in late May or early June. Another, Balio- 

 sus californica, was reared by Mr. Coquillett from larvae 

 mining in the western Ceanothus integerrimus. Anoplitis 

 inaequalis, has been bred from the white snake root, Eupato- 

 rium urticifolium, and from the wild sensitive plant, Cassia 

 nictitans. Another, Chalepus bicolor, was reared by Mr. 

 Pergande from the leaves of the panic grass, Panicum 

 macrocarpum. 



