The Biology of Maine Species of Altica. 193 



FOOD PLANTS OF THE LARVA OF THE ELM FLEA-BEETLE. 



(i) Eaten readily. 



White elm, red elm, basswood. 



(ii) Eaten indifferently. 



Corn, hazel, red oak, European gooseberry, mountain ash, 

 shad bush, wild strawberry, cultivated strawberry, wild 

 rose, cultivated rose, Japanese rose, choke cherry, red 

 cherry, wild plum, cultivated plum, bean, fireweed, marsh 

 fireweed, evening primrose, panicled dogwood, bunchberry, 

 low blueberry, tomato. 



(iii) Refused. 



Cultivated willow (!), heart-leaved willow, aspen poplar, 

 balsam poplar, sweet fern, gray birch (!), alder (!), 

 syringa, cultivated spiraea, apple, red currant (!), wood- 

 bine, red osier dogwood (!), sheep laurel, lilac, Joe Pye 

 weed. 



Natural Enemies. 



Fungous diseases. This species is susceptible to the same 

 fungous diseases as A. corni (see page 173). 



Insect enemies. But two species of insects have been found 

 preying upon the elm flea-beetle, one a parasitic and the other a 

 predaceous form. 



The writer has bred a single specimen of Celatoria spinosa 

 Coquillet from an adult elm flea-beetle. This is the same species 

 which he has bred in considerablv larger numbers from A. corni 

 (see page 173). 



The nymphs of one of the large soldier bugs (Podisus 

 modcstus) were found feeding on the larvae of this flea-beetle 

 in Orono during the summer of 1917. Neither of these insect 

 enemies was found in sufficient abundance so that they would 

 appear to be of much effect in controlling the species. 



Control. 

 Same as for A. corni (see page 173). 



