SIPHONOPHORA PISI. 
135 
Fuj^a. 
Coloured mucli as the larva. Wing-cases olive. 
The mealy coat often reveals a darker green stripe 
down the back of the insect. 
Winged viviparous female. 
Inches. 
Expanse of wing 0*360 to 0*380 
Size of body 0*090 X 0*035 
Length of antenn83 0*150 
„ cornicles 0*040 
Millimetres. 
9*14 to 9*64. 
2*27 X 0*88. 
1 * 01 . 
3*81. 
Very much of the colour of the larva. More or less 
glaucous. The antennae, like the nectaries, slightly 
vary in shades from pale green to olive. Abdomen 
very taper. Cauda less ensiform than usual in this 
genus. Wings ample. Insertions, cubitus, and stigma 
yellowish green. Thoracic lobes rather olive brown. 
Eostrum reaches to the second coxae. 
The emergence of the imago from the pupa is an 
interesting sight under the microscope. The rapid 
dilation of the insect by the absorption of air is to 
be noted. 
This is one of the most numerous of the field species 
of Aphides, and in some years is very destructive to the 
farm crops. It feeds on a large number of plants, but 
chiefly it infests the field pea, on the young shoots 
and leaves of which it clusters by thousands. Some 
years, however, the colonies are few in number. The 
winged form is less common than the apterous. 
Amongst the food plants named by Kaltenbach 
are Pisum sativum^ Lotus uliginosus, Lathyrus odoratus, 
Spircea ulmaria, Gapsella bursa-pastoris, &c. The 
glaucous female in PI. XIV was taken on the common 
nettle Urtica dioica. Passerini adds S. gei to the 
synonyms of S. pisi. 
