160 Aphides and Sanwflies [CH. 
living young as described above. In some cases the 
females are capable of living through the winter. 
Their life history may be shortly represented thus: 
Wingless females 
Several broods of wingless females ... Spring 
Winged and wingless females and 
Summer 
Several broods of winged and wingless 
females 
Males and females a8 ue .. Autumn 
1 
Eggs si wi at ... Winter 
The aphides have soft swollen bodies, the colour of 
which varies in different species and may be yellow, green 
or brown. The feelers are usually long, and the abdomen 
carries a pair of short tubes on its upper surface pointing 
backwards and slightly outwards. These are char- 
acteristic of aphides and are called “honey tubes” 
because of the sugary liquid they secrete. Aphides are 
covered with a waxy bloom which causes water to run off 
them. The winged forms have two pairs of membranous 
wings of which the front pair is much larger than the 
other pair and also considerably longer than the body 
of the insect. The males are smaller than the females. 
They all live by sucking the juices of plants and have 
long probosces for piercing and sucking. They often 
cause the leaves to curl in such a manner that the 
insects themselves are hidden away inside the curled 
leaf. They also excrete a sticky substance known as 
