286 THE CANADIAN ENTOMOLOGIST 



This will then leave the species as follows: 



Pterocomma populea (Kalt.) 



Synonymy: Aphis populea Kaltenbach. 



Cladohius popideus (Kalt) Koch. 

 Pterocomma pilosa Buckton (apterous form). 



Pterocomma farinosa (Del Guercio). 

 Synonymy: Cladobius farinosus Del Guercio. 



Pterocomma steinheili (Mordwilko). 

 Synonymy: Cladobius steinheili Mordwilko. 



Pterocomma salicis (L). 



Synonymy: Aphis salicis Linnc. 



Melaiwxauthus salicis (L) Buckton, Weed, etc. 

 Melauoxautherium salicis (L) Schouteden. 

 Pterocomma salicis (L) Wilson. 

 ? Pterocomma bicolor Wilson, not Oestlund. 



Pterocomma populifoliae (Pitch). 



Synonymy: Aphis popidifolia Fitch. 



Pterocomma pilosa Buckton (alatc form). 

 Cladobius populetis Pcrgande, not Kalt. 

 Cladobius rufulus Davidson. 

 Melanoxanthus bicolor Williams, not Oestlund. 

 Melanoxantherium rujulum (Davidson) Essig. 

 Pterocomma populea Wilson, not Kalt. 

 ? Melanoxantherium salicti Patch. 

 . Cladobius beulahensis Wilson, not Cockerell. 



Pterocomma flocculosa (Weed). 



Synonymy : Melanoxauth us flocculosus Weed . 



Melanoxantherium flocculosum (Weed) Schouteden 

 Pterocomma flocculosa (Weed) Wilson. 



