8*7 
quite probable, and corresponds with ray observations, of which, un¬ 
fortunately, I have no notes, but I certainly have noticed the winged 
specimens, and if I recollect rightly, apterous individuals also, on the 
tender twigs. 
Aphis pruni, Koch. The Plum-tree Aphis. 
A. prunifolice, Fitch. The Plum-leaf Aphis. 
I am satisfied that our species, which Dr. Fitch has named A. 
prunifolice, is the A. pruni of Koch, but not the A. pruni Fabricius, 
as Dr. Fitch rightly supposed, nor the A. pruni of Scopoli, which is 
probably identical with A. humuli of Schranck. 
This is much like the apple-leaf plant-louse both in appearance and 
habits, except that it selects the plum-tree as its food plant instead of the 
apple-tree. It is found on the underside of the leaves of our native 
and cultivated plums, wrinkling and destroying them. What is said 
in reference to the history of the apple plant louse will apply as a 
general rule, to this species, which does not appear to abound to the 
same extent as some of the species already named. 
This species appears to be quite variable, but the following taken 
chiefly from the original description by the author of the species, will 
probably enable the reader to identify it. 
The winged specimens measure about one-seventh of an inch to the 
tip of the wings ; the body is of a shining black color, except the 
abdomen, which is pale green with a black dot on each side of the 
two or three anterior segments ; a large dusky spot rather behind the 
middle ; tip of the abdomen acuminate ; honey-tubes cylindrical, reach¬ 
ing to the tip of the abdomen. The legs are pale, dull yellowish; „ 
antennae black, except at the base, where they are pale. Wings pel¬ 
lucid ; veins dusky, except the rib-vein. The venation does not appear 
to be as uniform as is usually the case in this genus. 
The larvae are more or less of a greenish white color, varying 
according to age. The wingless specimens are broadly oval in form ; 
the average length about one-sixteenth of an inch. 
Winged individual. —Antennae about as long as the body dusky or 
black; head and thorax black, a greenish ring usually around the 
neck, and sometimes slightly powdered or pruinose ; abdomen green 
with black dots on the lateral margins and usually a large black spot 
on the central portion reaching back to the honey-tubes, also two or 
three transverse black lines behind the honey-tubes; honey-tubes of 
moderate length reaching nearly to the tip of the abdomen, black; legs 
pale, dark at or near the joints. 
Wingless female. —Antenme scarcely as long as the body, basal joints 
dark, rest dull yellowish; head black; thorax and abdomen green, the 
former with two transverse dark lines, the latter with black marginal dots 
and a large black space on the central part; honey-tubes yellowish. Some 
specimens have the head greenish yellow and are without the large 
black spot on the abdomen. This sex has the body very broadly ovate. 
This species appeared early in the season on one of my plum trees 
but soon disappeared ; they were almost entirely black, this color pre¬ 
vailing to a larger extent than given by Koch. 
