



Vol. XLII. 



LONDON, AUGUST, 1910. 



No. 8. 



A KEY TO THE GENERA AND NOTES ON THE SYNONYMY 

 OF THE TRIBE CALLIPTERINI, FAMILY APHIDFD^. 



BY H. F. WILSON, U. S. BUREAU OF ENTOMOLOGY. 



With a view to correcting various incorrectly used terms of this group, 

 the author has made a careful study of American and European forms and 

 type species. So far as he has been able to determine from the specimens 

 studied, only a single American species can be placed in the genus 

 Calliptenis, which also includes but one European species, while the 

 majority of the American forms belong to the genus Myzocallis. A 

 detailed description of each type species has been given, and the 

 synonymy was made after a study of specimens for each genus involved. 

 It is hoped that the key for generic determination will fully cover all the 

 known American species. 



I am indebted in this paper to Prof C. P. Gillette, of Fort Collins, 

 Colo., who was kind enough to help me with the key for the genera. 



Tribe Callipterini. 



Antennae six segmented, variable in length, and usually quite slender ; 

 sixth segment with a more or less variable spur, which in some species is 

 short and stout, in others exceedingly long and slender. Beak short and 

 thick, wings long and slender, the cubitus with two forks. Nectaries 

 variable in size and shape, but usually short. Cauda usually globular at 

 the tip and constricted towards the base  beneath the cauda is the anal 

 plate, which is usually large and formed into two lobes. 



All of the species in this group are marked in such a way as to give 

 them a beautiful delicate appearance, and they are quite easily distin- 

 guished. The larvte are covered with fine bristles, each of which arises 

 from a minute tubercle. The sexual females have the abdomen consider- 

 ably elongated, and this elongation can be pushed into crevices where the 

 eggs are deposited. 



Key to Genera of Callipterini : 



1. Antennal tubercles prominent ; antennae always exceedingly long. .3. 



2. Antennal tubercles wanting or very small ; antennse variable in length, 



sometimes shorter than the body 4. 



