18 



BULLETIN 276, U. S. DEPARTMENT OF AGRICULTURE. 



filament of segment VI longest, it being noticeably longer than III; 

 segments I and II of a darker green color than body, III with the 

 extreme base pale, the remainder of that segment brownish with the 

 extreme tip black; IV pale brown at base gradually changing to 

 blackish brown toward the apex, the extreme tip black; V and VI 

 blackish to black, bearing a moderate number of rather short, fine 

 hairs; segment III with 11 to 22 (one apparently abnormal specimen 

 had but 9 and 10 sensoria, respectively, on its two antennae), with an 

 average of 15.5 for 36 examples examined, circular sensoria arranged 

 in a row but not extending quite to the tip, the distal one-fifth of the 

 segment bare, the usual distal sensoria on Y and base of VI. Beak 



Fig. 6. — Macrosiphum pisi: Winged female of viviparous general ion, much enlarged; a, antenna, b, cornicle, 

 and c, cauda, of same, more enlarged. (Original. I 



not quite reaching coxae of second pair of legs. Wings clear, veins 

 slender and brownish, the second branch of the media varying some- 

 what but usually about equidistant from tip of wing to the point 

 where the media first branches; hind wings with normal venation. 

 Legs long and slender; femur pala green on basal half, becoming 

 dusky to blackish toward tip; tibia pale greenish with a faint brown i-h 

 tint and the apex black; tarsus black. Cornicles (fig. 6, h) long and 

 slender, reaching beyond tip of cauda, widest at the base, basal third 

 concolorous with the abdomen, remainder dusky and the extreme 

 tip black, imbricated, and no sign of reticulation at the tip. Cauda 

 concolorous with the abdomen. 



