4 Mr. F. Walker’s Descriptions of Aphides. 43 
VIII.— Descriptions of Aphides. By Francis WALKER, F.L.S. 
| [Continued from vol. ii. p. 431.] 
} 56. Aphis dirhoda, n.s. 
_ ‘This species feeds on the rose with Aphis Rose, and is some- 
times far more numerous than that species in the spring and in 
the autumn, but its appearance is less regular ; it frequents various 
. species of rose both wild and cultivated, such as Rosa centifolia, 
4 ~ R. canina, R. eglanteria; and in the summer it migrates to dif- 
___ ferent species of corn and of grass (Secale, Triticum, Avena, Hor- 
deum, Bromus, Dactylis, Holcus, and Poa), and it fixes itself on 
the blades of these plants, whereas A. Avene prefers the flowers. 
Aphidius Avene, an Allotria, Asaphes enea, and Megaspilus Car- 
penteri, ave its parasites, and these will be more particularly 
noticed in another part of these descriptions. 
The viviparous wingless female. This sometimes rests through 
a severe winter under the rose-leaves without being injured, and 
begins to multiply very early in the spring : it is oval, and pale 
greenish yellow : the feelers have pale brown tips, and are about 
one-fourth of the length of the body: the eyes are dark red: the 
mouth and the nectaries are pale yellow with brown tips, and 
the latter are about one-sixth of the length of the body : the tip 
of the abdomen is brown : the legs are shorter and more slender 
than those of Aphis Rose, and the feet are pale brown: it is also 
distinguished from that species by its paler colour, its shorter 
feelers, and its larger body ; the two kinds may often be seen 
together on one rose-twig, each surrounded by its respective little 
ones. — 
- The front is prominent in the middle between the eyes: the 
tubercles on which the feelers are seated are rather less developed 
than those of the preceding species ; the fourth joint of the feelers 
is much shorter than the third; the fifth is shorter than the 
fourth ; the sixth is not half the length of the fifth ; the seventh 
is nearly as long as the third. 
The viviparous winged female. While a pupa it much resembles 
the wingless female in colour : its wings are unfolded in April or 
__ May, and then it is pale green: the chest is buff; its lobes are 
_ pale brown : the feelers are brown, green at the base, and much 
shorter than the body; the fourth joint is shorter than the third, 
and the fifth is shorter than the fourth; the sixth is nearly half 
_ the length of the fifth ; the seventh is a little shorter than the 
third : the eyes are dark brown: the mouth has a brown tip: the 
nectaries are about one-sixth of the length of the body: the legs 
r are pale yellowish green and rather long; the feet and the tips of 
the thighs and of the shanks are brown : the wings are colourless, 
