THE PLUM. 
AFFECTING THE LEAVES. 
Wrinkling and distorting the leaves; a black, shining plant-louse, with a pal 
green abdomen. 
Tub Plum Leaf-locse, Aphis Pr uni folia:. 
The Aphis which infests the under sides of the leaves of our 
native and also our cultivated plums, curling and distorting 
them, is one of the most variable species which I have met with 
pertaining to this family. And so much does it disagree with the 
accounts which we have of the plum louse of Europe (JJpkis 
Pruni, Fab.) that I am constrained, though with some doubt, to 
record it as a distinct species. The descriptions given of the 
plum louse are quite discordant. Walker (List of British Mu¬ 
seum, p. 989) describes the viviparous winged female as dark 
gray with nectaries hardly projecting above the surface of the 
abdomen, whereas, in all the winged individuals of our American 
insect which have fallen under my observation, the nectaries are 
cylindric, nearly or quite equalling the tip of the abdomen. It 
further disagrees with his description, in having the third vein 
of the fore wings not much further from the second at tip than at 
base, and the fourth vein strongly instead of slightly curved. 
Fabricius (Ent. Syst. iv. 213) describes the European insect as 
having a greenish body, antennas and legs, with a darker abdo¬ 
minal stripe and point each side of the base, and the margin 
plaited. Unless this description is very faulty our plum louse 
must be distinct, it having the thorax and antennas uniformly 
black, and no plication on the sides of the abdomen; nor can the 
large dusky spot be termed a stripe. Since the foregoing was 
written I notice that M. Arayot (Annals Entom. Soc. 2d series, v. 
476,) gives the top of the head and the thorax of the plum aphis 
as brown and d.usted with a white powder. This more strongly 
