52 



New York Stair Collrfir of Forestry 



Family APHIDIDAE 



This larwe and exceedingly important family has been given less 

 attention than some of the other families, partly because the most 

 important species have received extended investigation, partly due 

 to the effort to clean up details of life history for some of the 

 destructive but little known species in other families. No attempt 

 has been made to collect the species occurring in the Cranberry 

 Lake region. 



The group is of remarkable interest on account of its unusual 

 mode of reproduction, its enoi-mous rate of multiplication and the 

 many puzzling phases of its attacks oji different hosts, seasonal 

 migrations, alternate hosts, etc., which cannot be takeii up in detail 

 within the limits of this paper. 



Ecologically, they may be characterized as uniformly plant 

 feeders. Most of the species, pi-actically all for this region, attack 

 leaves, Iwigs or smaller bi-anches. They multiply so rapidly and 

 form such large colonies that the drain on the plant from the 

 constant sucking of sap frequently results in wilting or withering 

 of plant infested. !Snch sjiecies as the Pine chermes. Alder blight 



Fiy. 21.- - Alder lilii^lil. Ptiii pJi i(jiin h'sNchilo : o. iiiiicli en- 

 larged; /;, alnuit natural size. J'liotu hy Drake and Kivaz. 



