332 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 11 
Aphis baker/ X 80 
Fig. 13 
31; sensoria somewhat tuberculate, joint III with about 36, joint IV with about 12, 
and joint V with about 6 oval or circular sensoria; length of fore wing, 2.75 mm.; 
venation normal; hind tibia, 9 mm. long, swollen in proximal third and with about 
15 to 20 oval or circular sensoria. See figures 20-23. 
Alate Sexupara or Fall Migrant. The fall migrants, so far as can be deter¬ 
mined from our alcoholic material, differ from the spring migrants by having a few 
more sensoria on joints 3 and 4 of the antenna and much fewer sensoria on the hind 
tibia, about 5 to 10 in the examples studied. Examples taken October 1, 1917, on 
Amelanchier leaves at Fort Lewis, Colorado. 
Fig. 12. Aphis helichrysi. 1, cauda; 3, cornicle; 4, antenna of apterous virgogenia; 
2, cornicle; 5, antenna of alate virgogenia. 
Aphis viburnicola. 6, antenna; 7, vertex; 8, cornicle; 9, cauda; 10, hind tibia of 
spring migrant; 11, antenna of fall migrant; 12, antenna of male. 
Aphis sensoriata. 13, 14 and 16, antennae; 15, hind tibia; 17, cauda; 18, cornicle 
of adult apterous virgogenia; 19, tibia of nymph; 20, antennae; 21, cornicle; 22, hind 
tibia of alate virgogenia; 23, hind tibia of alate sexupara; 24, antenna of male; 25, 
antenna; 26, hind tibia of oviparous female. 
Fig. 13. Aphis bakeri. 1, antenna; 3, cornicle of apterous virgogenia; 2, cauda; 
4, cornicle; 5, antenna of alate virgogenia; 6, antenna of male; 7, antenna; 8, hind 
tibia of oviparous female. 
Aphis cratcegifolios. 9, antenna; 10, vertex; 11, cauda; 12, cornicle of alate virgo¬ 
genia; 13, antenna of sexupara. 
All figures enlarged 80 diameters. Original, Miriam A. Palmer, Delineator . 
