58 
Siphonophora asclepiadis ? Fitch. Milkweed Aphis. 
Found at Fort Dodge, Iowa, September 1st, on the leaves of the 
large Milkweed (Asclepias cornuti,) generally on the under side, or on 
the 3 upper side, near the base of the leaf. They are generally found 
near the top of the plant on the young and tender leaves. 
I o-ive this as identical with the species described by Dr. Fitch with 
some doubt, if it should be different it may be named S. asclediadi- 
folii. I herewith present Dr. Fitch’s description. 
“It inhabits the under surface of the leaves of the common Silk- 
weed. Black; abdomen pale green; two rows of compressed dusky dots 
on each side, three in the lower and five in the upper row; honey- 
tubes nearly reaching to the tip of the abdomen; veins of the foie 
wings brown, the costal or marginal one whitish; stigma smok^-white. . 
Length, 0.15 inch.” ■ 
Wingless females.— About medium size; antennae nearly as long as 
the body; honey-tubes reaching beyond the tip of the abdomen, largest 
at the base, cylindrical. The general color very dark green, many so 
dark as to appear black, but usually the green shows distinctly on the 
abdomen, the true color appearing to be green or dark green with 
dusky shadings; under side dark green; antennae transparent whitish, 
except near the tip where they are dusky; legs clear, transparent white, 
except the tarsi, which are black; honey-tubes black; tail distinct, but 
short slender and apparently dark green. Body ovate and convex. 
The young larvae are pale greenish. Those which will acquire wings 
are easily distinguished from other larvae while quite young, being more 
flattened on the back, more elongate and oval in shape and the honey- 
tubes are not more than half the length of those of the apterous vivipa¬ 
rous females. These and the pupae they produce are yellowish or orange 
colored, sometimes greenish. 
Winged individuals .—Found with the above, and as 1 am fully sat-. 
isfied belonging to the same species. 
Antennae a little shorter than the body, reaching about to the base 
of the honey-tubes; the tubercles on which they stand have the inner 
margin more than usually prominent; the third joint shows a few pus¬ 
tulous spots. Front between the antennae appears to be prominent and 
almost pointed; the tubercle on the hind portion of the eye very prom¬ 
inent. Honey-tubes cylindrical, reaching beyond the tip of the abdo¬ 
men, length about one-fiftli that of the body; tail distinct but not very 
prominent, somewhat narrow and conical, not more than one-fourth as 
long as the honey-tubes. General color yellow or greenish yellow. 
Antennae dusky, third joint pale at the base; head dark; neck \ellow, 
thorax dark above and beneath; abdomen yellow; honey-tubes dinky 
in the middle, paler toward the base and tips; tail yellow; the tips of 
the tibiae and tarsi dark. 
Siphonophora erigeronensis. Tlios. Aphis of the Canada flea-bane. 
Found during August at Carbondale, Illinois, on the dower stalks of 
the Canada FI ethane ( Erigeron Canadense). Observed first August 
16th, some were then in the winged state; again noticed August -»tn. 
