333 
Mr. F. Walker^s Descriptions 0 / Aphides. 
it is oval, yellow, rather flat and hairy, and has four rows of 
black spots on the back, and these spots are often confluent so 
as to form bands : the feelers are black, and nearly as long as the 
body, but sometimes they are very much shorter ; the base of 
each joint is yellow ; the fourth joint is very much shorter than 
the third, but more than half its length ; the fifth joint is as long 
as, or a little longer than the fourth ; the sixth is a little shorter 
than the fifth ; the seventh is more or less shorter than the fifth, 
and its base does not occupy the whole breadth of the tip of the 
latter : the fore-chest is broader in proportion to its length and 
narrower in front than that of the winged female : the abdomen 
beneath has a shield-like plate on each side near its tip : the hind- 
shanks are broad ; the tips of the fore-thighs and of the middle- 
thighs, the hind-thighs from the middle to the tips, and the base 
of the hind-shanks are grayish black : the feet with the excep- 
tion of the base are black. The eggs which it bears are about six 
in number. 
1st variety. The abdomen above is nearly black, all its spots 
being confluent. 
While this oviparous female is employed in laying eggs, the 
viviparous mother still continues to bring forth young ones which 
quickly perish by the fall of the leaves where they are seated ; 
these leaves while fading on the tree are frequented by little 
white half-transparent Acari. 
The wingless male. It has much resemblance to the wingless 
female, with which it pairs in September. 
The winged male. This appears in September and October, and 
then pairs with the wingless female : it is brown : the head and 
the chest are slightly marked with yellow : the abdomen is yellow, 
and has a brown border : the feelers are black, and much longer 
than the body : the legs are yellow ; the hind-thighs, except the 
base, the base of the hind-shanks, and the tips of the feet, are 
black ; the knees, and the tips of the shanks are gray : the tips 
of the wing-veins are less shaded than those of the female usually 
are, but the colour of the body is darker than in that sex. 
Seventh Group. 
The viviparous wingless females appear in this group, but it 
is distinguished by the great predominance of the winged female, 
and is scattered and not clustering on its habitation. The veins 
of the wings are usually more or less clouded. 
9. Aphis Betulicolay Kaltenbach, Mon. Pflan. i. 44. 
The viviparous wingless female. This appears in July, but is of 
rare occurrence ; it is pale orange and oval ; the back is slightly 
convex and rather hairy : the middle-chest and the hind-chest 
