62 
domen green, with six or seven transverse dark bands, the middle 
band being the broadest. Four lateral spots on each edge; cornicles 
green with black tips. Antenna 1 long and thin. Legs pale yellow 
ochre, with black femora and tibia? points. Wings with yellowish in¬ 
sertions and grayish stigma; other veins brown. 
u This species *feeds on many plants, particularly Lctctuca oleracea , 
Lactuca scariola . (garden lettuce) Sonchers , Crepis and other plants. It 
may also be found on the leaves of Ribes grossularia and Ribes nigrum. 
The branching of the veins is somewhat variable, and the length of 
the antenna? also differs in some individuals. The insect is commonly 
met with throughout the summer. It does not answer the description 
given by Koch of his S lactncce, which certainly must be a different 
species.” _ ' 
1 The following description was taken from specimens found on com¬ 
mon garden lettuce at Carbondale, Illinois, in *1878: 
Wingless female. —Antenna? long and slencler, extending back quite 
to and even beyond the tip of the abdomen; body of a rather long 
ovate form, rather narrow in front, thorax not much broader than the 
head. Legs very long; honey-tubes very long and slender, in some 
specimens distinctly though not strongly enlarged in the middle, ex¬ 
tending beyond the tip of the abdomen, equal in length* to one-fourth 
the length "of the body; tail very prominent, slender and elongate con¬ 
ical, about half the length of the honey-tubes; beak rather short, 
reaching only to the insertion of the middle legs. The hinder portion 
and sides of the abdomen of some individuals are more or less 
roughened, and sparsely covered with little tufts of hair. 
Color.—Body rather pale pea-green, many specimens showing from 
one to three deeper green longitudinal stripes on the abdomen; 
head pale; legs, antenna?, honey-tubes and tail transparent white? 
tarsi, and the antennal sutures in some specimens, dark. 
Length of body about one-tenth of an inch. 
An imperfect winged specimen found among these, whether the 
same species or not, I am unable to say, had the body dull black, 
smaller in size than the wingless; wings and other characters showing 
it to belong to this genus. Obtained in May. 
It is more th^n probable that this and several other species found 
on garden vegetables will ultimately be found to be but varieties of 
one or two distinct species, the varietal characters probably being 
caused by the difference in plants and the changes produced by culti¬ 
vation. 
Siphoxophora polygoxi. Walk. The Knot-weed Aphis. 
A plant-louse found during the early part of summer on the com¬ 
mon knot-weed ( Polygonum persicariae). As this species of knot-weed 
is common in England as well as here, our species is therefore in all 
probability identical with the English species. I searched carefully du¬ 
ring the past summer for specimens but was unable to find any, and 
am not aware that the species has been observed in Illinois, although 
it has been found in the United States. 
The following brief description is from English authors: 
Winged viviparous female. —Yellowish or greenish; head and thorax 
unusually broad; antenna? longer than the body; honey-tubes long, 
