322 A finals Entomological Society of America [Vol. Ill, 



— Antennae much shorter than the body, nectaries slightly constricted at 



the tip Coloradoa 



Antennae shorter than the liody and with but five segmented antennae. 



Nectaries short and cylindrical Cerosipha 



V. Nectaries prominent and readily distinguishable. . \'l. 



— Nectaries very small and obscure VII. 



\'I. Antennae shorter than the body, nectaries very stout and tapering. Cauda 



short and thick Pergandeida 



— Antennae shorter than the body, nectaries very short in above l>ut slinder 



and swollen in the middle Hyalopterus 



\'il. Antennae much shorter than the body, nectaries cylindrical and as liroail 

 as long. Cauda much longer than the nectaries and tapering. Brachycolus 

 Antennae longer than the body, nectaries barely distinguishable, the en<l 

 being trumpet shaped. Cauda not as long as wide and triangular. 



Microsiphum 



Antennae shorter than the body, nectaries little more tlian raist<l rin>.;s, 



and not flanged like the preceding genus Cryptosiphum 



Gen. Liosomaphis Walker 



type A. berberidis Kaltenbach 



Antennae shorter than the body and with indistinct anten- 

 nal tubercles, spur of sixth segment about the same length as 

 the segment; first segment gibbous on the inner side. Body 

 elongate, abdomen robust, wings long and broad, cubitus twice 

 forked. Nectaries about one fourth the length of the body 

 and strongly clavate. Cauda less than one half the length of 

 the nectaries and sharply tapering. Anal plate broadly rounded. 



Gen. Hyadaphis Kirkaldy 



Syn. Siphocoryue /j^-vj^a-/;// preoccupied. 



Antennae nearly as long as the body, third segment shorter 

 than the spur of the sixth. Head with a slight projection at 

 the inner base of each antenna. Body elongate, wings long 

 and broad, venation regular. Nectaries about one fourth the 

 length of the body and clavate in the middle. Cauda triangular 

 short and rounded at the tip. Anal plate broad half moon 

 shaped. 



Gen. Aphis Linnaeus 



type A. sambuci Linn.? 



Antennae as long as the body, spur of sixth segment three 

 times as long as the segment and as long as the third segment. 

 Body elongated, abdomen robust. Wings broad and stout, 

 with cubitus twice forked. Nectaries about one fourth the 

 length of the body, somewhat slender and tapering. Cauda 

 one fourth the length of the nectaries, stout and set on a Ijroad 

 base. Tip broadly rounded. 



