288 THE CANADIAN ENTOMOLOGIST 



In the synonymy of populea Kalt., the third reference, Cladobius 

 should be omitted and Kalt. inserted in p^arenthesis after populeus. 

 Whether or not the word was written thus, and not Cladobius, I 

 have been unable to prove. The first edition of Passerini's Gil 

 Afidi was published in 1857. I have not been able to see this nor 

 the 1860 Parma edition. Wilson's reference, however, is incorrectly 

 written. So also is his reference to Aphidida* Italica\ 1863. Pilosa 

 Buckton is cited twice. In the second citation it is indicated that 

 the species was not described as a Pterocomma, but was referred 

 to that genus by Wilson. In writing the name populea in connection 

 with Pterocomma, Kalt. should be in parenthesis. 



On page 355 Aphis salicis Harris is discussed. This is a mis- 

 print for salicii Harris, named on page 191 of the first edition of 

 Harris' work. The same is seen in the citation of Oestlund, etc. 

 In listing smithice as a Pterocomma, Moncll, which is incorrectly 

 spelled, should be in parenthesis. 



In the list of species on page 347, the genera in which they 

 were originalh- described are placed in parenthesis between Ptero- 

 comma and the specific name. This is the method given in the 

 international code for the indication of subgenera. 



All of these little details are very minor matters, but they 

 arc here mentioned for purposes of reference. 



Key to the Species of Pterocomma 



1. Cornicles without a distal flange and abruptly constricted at 



the distal extremity floccidosa. 



Cornicles with a distal flange and not so abruptly constricted at 

 their distal extremities 2. 



2. Cornicles about twice as long as their greatest 



diameter smithice. 



Cornicles much more than twice as long as their greatest 

 diameter 3. 



3. Cornicles about equal in length to the hind tarsi 4. 



Cornicles much longer than the hind tarsi 6. 



4. Beak reaching to the cornicles or nearly to them populea. < 



Beak reaching only to the hind coxa? or not quite to them 5. 



