162 
as in most of the plant-lice. They are smoky-transparent with a more 
dusky spot or stigma on the outer margin between the tip of the rib- 
vein and the outer edge, the rib-vein being perfectly straight and not 
curved as in the other plant lice to give a greater width to this stig¬ 
ma spot. In addition to the rib-vein the fore wings have ohly three 
oblique veins, all of which are straight and black. The first of these 
is placed forward of the middle of the wing and runs from the rib- 
vein to the inner margin. The last one runs from the stigma to the 
tip of the wing and is abortive or imperceptible at its base where it 
starts from the stigma. The middle vein is parallel with this last and 
starts from the first vein above its middle and reaches the inner mar¬ 
gin equidistant from the tips of the other two, its base being abortive 
for a short distance. The hind wings form a very eonpicious angular 
point on the middle of their outer margin and have a longitudinal 
rib-vein but are wholly destitute of any oblique vein running from it 
to the inner margin. (Fitch). 
Found on the leaves of the shag-bark hickory (Carya alba). 
Phylloxera cary^even^e. Fitch. 
Syn. Pemphigus carycevence. Fitch. Hickory-vein Gall-louse. 
Forming plaits in the veins of the leaves, which project up from 
the surface in an abruptly elevated keel-like ridge upon the upper side 
of the leaf and with a mouth opening on the under side, the lips of 
which are woolly and closed. 
Although the aphis which produces these plaits in veins of the lea 
ves is unknown to us in its winged state, its work will suffice to dis- 
- — -- - —- ZD J 
tinguish it from other species. The plaits occur mostly near the 
middle of the leaf, upon one side of the mid-vein occupying the bases 
of the lateral veins, two or three of which are commonly enlarged in¬ 
to the excrescences or galls, which put up in keel-like ridges from a 
quarter to a half inch in length. These ridges are of a pale yellow 
color, turning brown and becoming dry and dead after a time, 
frequently before they perish the portion of the leaf between them 
withers and turns brown, in which case the inhabitants of the gall 
forsake it. being no longer able to obtain a due supply of nourish¬ 
ment from its walls. The lips of the mouth which opens on the undei 
side of the leaf are covered with white or pale tawny yellow wool 
They are pressed together, but a small orifice is open at their outei 
end through which some of the young lice frequently crawl from the 
interior of the gall and station themselves upon the under surface of 
the leaf by the side of the mid vein. The lips are readily drawn 
apart, exposing the cavity within, the walls of which are covered with 
minute wingless, females and their eggs and young. The females art 
egg-shaped, broadest anteriorly and tapering behind to an acute but 
not an attenuated point. They are 0.03 long, 0.02 broad, very palt 
yellow and at the tip watery white. The eyes appear like two minutt 
brown dots widely separated, the head being short and broad with th< 
transverse sutures between it ai.d the other segments of the body vet*] 
slight and indistinct. The legs and antennae are short,and tinged witl 
