THE CANADIAN ENTOMOLOGIST 237 



about twice as long as the 4th, with 17-20 sensoria over its whole 

 length, but not so markedly tuberculate as in kocliii and cratcsgi, 

 but with many more sensoria than in potni; 4th segment with 

 10-14 sensoria, the same length as the 5th ; the 5th with 0-6 sensoria, 

 including the usual sub-apical one; the 6th about as long as the 

 4th and 5th; the last three imbricated. Cornicles rather short, 

 either brown or pale greenish brown, somewhat swollen in the 

 middle or irregularly cylindrical constricted at the apex, which is 

 more or less flared and, to some extent, constricted at the base; 

 in some specimens the cornicles are almost black. Legs dark, 

 except base of femora and most of the tibiae, which are pale greenish 

 brown to pale green or yellowish. Base of wings green to yellow. 

 Length 1.5 to 2 mm.; wing expanse 6 to 7 mm. 



Return alate migrant: 



Very similar to the former, but appears to be smaller in most 

 cases, and the 5th antennal segment has seldom more than the 

 usual sub-apical sensorium, but in an occasional specimen 1-2 

 extra ones may occur. The abdomen more variable, green, yel- 

 lowish or pale brown. 



Variation in sensoria of alate female. 



The apple spring migrant may often have no sensoria on 

 segment 5, except the usual sub-apical one, but now and then from 

 1-3 may occur. This also seems to be the case with ''fitchiV in 

 America. Those from oats and wheat, the return migrants to the 

 apple and pear, usually have none but the sub-apical one, but 

 now and then 1-3 may also occur. In America it seems that this 

 segment usually has a few sensoria. Pergande figures the second 

 generation — the migratory female — with sensoria on segment 5 

 and states that segment 3 is always strongly tuberculate, frequently 

 also 4 and sometimes also more or less 5 (Bull. 44, D. E., U. S. 

 Dept. Agri.). 



Apterous viviparous female: 



Green to yellowish green with often more or less distinct 

 mottled areas or dark green median and lateral lines; oval. Eyes 

 black. Antennae green, dusky at the tips. Cornicles greenish 



