Aphids Injurious to Orchard Fruits, Etc. 85 
These winged ones leave the plants, and we have not been able to 
trace them farther. They begin to appear early in May. 
The wingless forms carry on the infestation and in September 
and October the sexed forms appear. The male is very small and 
wingless and is slightly darker than the ordinary wingless form. 
The egg-laying female is somewhat larger than the male and also 
wingless. These mate and the female lays her eggs on the twigs a 
short time later. 
THE ORNAMENTAL CURRANT APHIS.! 
‘The wingless forms of the ornamental currant aphis are pale greenish 
with the honey tubes dusky at the tips. The winged forms are sim- 
ilar in color with pale brownish lobes on the thorax. The egg-laying 
female is orange in color with pale yellowish spots, while the abdomen 
of the male is dark. 
SEASONAL HISTORY. 
This species usually occurs on the ornamental currants. The eggs 
hatch in the spring and numerous generations of wingless forms are 
produced. By August these are present in large numbers on the 
tender terminal twigs and to a less extent on the undersides of the 
leaves. Winged forms appear in September or earlier and ants are 
found attending the insects. Early in October the orange, wingless, 
egg-laying females may be found mating with the winged males and 
the eggs are laid shortly afterward. 
THE WESTERN CURRANT APHIS.? 
This species lives on the flowering currant in California, on which it 
makes curls or blisters similar to those produced by the currant aphis. 
The wingless form is green or yellowish green. The winged form is 
green with black head and thorax. The egg-laying female is whitish- 
yellow and the male red. 
SEASONAL HISTORY. 
The eggs are supposedly laid on the twigs and the stem-mother 
appears very early in the season. The winged forms begin to appear 
in March and the male and egg-laying female may be found as early 
as the month of May. 
THE DOGBERRY APHIS.* 
The dogberry aphis is very like the Houghton gooseberry aphis. 
It was found on the prickly gooseberry or dogberry and occurs also on 
the Buffalo currant (Ribes aureum). It differs from the Houghton 
gooseberry aphis in having fewer pores or sensoria upon the antenne, 
and less distinctly knobbed hairs. Its life history is not fully known. 
1 Macrosiphum ribiellum Davis. 2 Myzus ribifolii Davidson, 8 Myzus cynosbati (Oest,). 
