BULLETIN 273 

 THE BIOLOGY OF MAINE SPECIES OF ALTICA.* 



William Colcord WooDS.f 



SUMMARY 



The flea-beetles commonly classed as Altica ignita 111. form 

 a composite group of closely related species. Three species of 

 the group are named and described in this bulletin: A. corni, a 

 black species occurring on dogwood, A. rosae, a cupreous species 

 occurring on the wild rose, and A. ulmi, a greenish or bluish 

 form found on the elm. The life histories of all three are very 

 similar. They hibernate as adults which, coming out from 

 their winter quarters in late spring, pair and deposit eggs on 

 the leaves of their respective host plants in June and July. The 

 larvae which hatch from these eggs feed on the leaves, skele- 

 tonizing them. In all cases there are 3 larval instars averaging 

 about 4 days each. When full grown, the larvae enter the 

 ground where they transform, spending about 5 days as pre- 

 pupae and 9 days more as pupae before emerging as adults. 

 There is but one generation each year. 



The blueberry flea-beetle, A. torquata LeC, belongs to the 

 carinata group. At least in this species the winter is passed in 

 the egg stage. The larvae hatch in late May, and feed on the 

 opening buds of the blueberry and later on the flowers and 

 foliage. They do great damage when they are abundant. As 

 in the ignita group, there are 3 larval instars, and the larvaL 

 life lasts about 12 days. The larvae when full fed enter the soiL 

 to pupate, spending about 6 days as prepupae, and 10 or 11 

 days as pupae, before the adult beetles emerge. The adults feed 

 freely all summer on the leaves of the blueberry, but do not 

 survive the winter. In July they deposit their eggs, probably 



*Papers from the Maine Agricultural Experiment Station : Ento- 

 mology No. 100. 



tMember of the Station Summer Staff. 



