148 
construction of & new genus, yet its external characters appear to be 
decidedly Pempliigian. 
Winged Specimens— Antennae very short, not more than three times 
the length of the head, not reaching quite to the end of the thorax; 
rather stout; third joint longest, rather longer than the fourth and 
fifth united; second, fourth and fifth about the same length; sixth 
about two-thirds the length of the third, with a short blunt spur at 
the tip; the third joint usually presents about six little transverse 
wrinkles, or pustules. Anterior wings with the third discoidal vein 
simple (not forked); very thin and delicate but slightly smoky; veins, 
with the exception of the sub-costal very slender and pale brown; the 
subcostal is rather broad and brownish; costa semi-opaque and brown, 
the first and second discoidal veins arise usually from the same point, 
but in some the space between them is distinct, first nearly straight, 
second curving slightly very oblique and diverging; third vein obso¬ 
lete at the base, (usually) straight; fourth curves, slightly at the base, 
rest straight. Stigma elongate, fading gradually into the subcostal at 
the base and rounded behind. 
The above description is from the mounted specimens, when living, 
the veins of the wings are dark. 
In the hind wings, the sub-costal vein curvers very strongly at the 
point where the two branch veines arise, so that the second vein 
appears to form its extension. In one specimen, the second branch 
vein is distinctly forked; in some cases the two branch veins appear 
to arise from the same point, in others they are distinctly separated. 
Beak reaching slightly beyond the base of the middle legs. 
No wingless specimens obtained. 
Body apparently black, but covered when living with a bluish- 
white cottony substance. No honey-tubes. 
Size small. 
Found on the underside of the leaves of the common raspberry, 
(Pubus occidentalis) along the mid-rib. 
It is possible that these specimens were accidently on the raspberry, 
they closely resemble that found by Profs. Bundy on Populus trem- 
uloules , which I have considered provisionally as belonging to Pem¬ 
phigus populicaulis . 
The Poplar-leaf Gall louse. Pemphigus populicaulis. 
a The incipient gall on the under side of the leaf, b, The corresponding bulge on the 
upperside. c, The fully formed gall, showing the lips slightly separated, so as to per- 
