251 
Mr. F. Walker^s Descriptions of Aphides. 
1st variety. Green, with two dark green stripes along the back. 
2nd var. AVhite, with two bright green stripes along the back. 
3rd var. Whitish green. 4th var. Pale green. 5th var. Dark 
green. 6th var. Yellowish green. 7th var. Yellow. 8th var. Pale 
red. 9th var. Dark red. 10th var. Nearly black. 11th var. 
With a broad pale stripe on each shank, and a narrower band at 
the base of each thigh. 
The wings are unfolded soon after the middle of April, or 
somewhat later ; the insect is then long, slender, active, rather 
flat, and of a bright yellowish green colour : the breadth of the 
head is about twice its length ; there are two impressions near 
together on its disc : the forehead is concave, and has a slight 
protuberance on each side : the feelers are slender, setaceous, 
brown, green at the base, and a little longer than the body ; the 
first and the second joints are very short, and the former is thick ; 
the third is very long ; the fourth is much shorter than the third ; 
the fifth is thick at the tip, and nearly as long as the fourth ; the 
sixth is obclavate, and about one-fifth of the length of the prece- 
ding joint ; the seventh is much more slender than the fifth, which 
it equals in length ; it is sometimes reddish brown : the eyes are 
bright red, and behind each of them there is a small detached 
lobe which supports a few facets like those of the proper eye ; 
this structure and the form of the chest are common to the genus : 
there are three eyelets on the crown ; one in the middle and in ad- 
vance of the other two : the mouth is pale yellow with a brown 
or a black tip, and just reaches the base of the middle legs ; it 
is the sheath of three very slender bristles which are put forth to 
pierce the plant when the insect sucks : the fore-chest is large, 
angular, and well-developed ; its breadth is about twice its length ; 
it has four furrows, and of these the two inner converge towards 
the fore-border and the two outer towards the hind-border : the 
middle chest is smooth and shining; its lobes and the disc of 
the breast are brown ; the corselet has a triangular lobe in front 
and another behind, and an irregularly-oval lobe on each side ; 
the scutcheon is short-obconical : the abdomen is spindle-shaped, 
slightly convex, not shining, and is furnished with a few hairs : 
the nectaries are seated on each side of the hinder part of the 
abdomen ; their tips are brown, and they are as long as one-fourth 
or as one-fifth of the body. Mr. Haliday has favoured me with 
the following information respecting these organs, through which 
the Aphides pour forth streams of honey : — It appeared to me 
that the row of spiracles send off internally from each a delicate 
membranous tube without the spiral coil, but soon ramifying into 
the ordinary tracheae, and that the nectary is not the regular 
spiracle of the segment in which it is placed, but that this is also 
present a little lower and more forward, and that the nectary is 
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