- 1918. BASHAMBAR DAS : The Aphididae of Lahore. 201 
Cornicles very small, cylindrical, black. 
Cauda round, on which the usual constriction is faintly marked ; more than half 
the length of the cornicles. 
Genital plate much in advance of the anal. 
Legs short; tarsi, ‘‘ankles’’ and ““knees’’ black, the rest brownish. 
Hind tibiae stunted and swollen in the middle, both ends narrow; there is a 
comparatively small number of indistinct sensoria scattered over the central dark 
portion ; the ratio of its length to the hind tibiae of an apterous viviparous female is 
about 7 to 11, as shown in the diagram. The sensoria mostly have a single contour, 
they number about fifty. 
- Rostrum reaches beyond second coxae. 
Measurements :-— 
Body eh bet 73202070. mm. 
Antennae i aes 27 705mm: 
Cornicle oH oF AUOT AMES 
' Cauda / OLOQi ase 
Eggs shining black, lighter when first laid; about ‘5 mm. or less in length. They 
can just be made out as dark specks with the naked eye. 
Life-history.—The leafy ‘spurs’ of the pear begin to unfold after the second 
week of February ; the flowers are out a little earlier. The foliage period runs into 
March. The eggs of this Aphid hatch about this time and begin to attack the young 
developing leaves. As the leaves are expanding, the presence of one or more of the 
“ stem-mothers’’ so modifies the process that the two edges of the leaf remain 
adhering to each other, and do not separate even when it is quite mature. Thus 
an inflated kind of pod results inside of which the Aphids multiply quickly. Such 
pseudogalls are generally open near the ends, and one often sees sometimes every leaf 
on a young branch affected in this manner. 
_ Many generations of purely apterous females are produced, and it is very difficult _ 
in the following months of March and April to secure the alate females. Even for dis- 
persing the colonies it is the apterous ones that move out for considerable distances. 
In May the last generation become winged, if they are not already destroyed by 
numerous predaceous and parasitic insects. Every individual on getting wings flies 
off and does not breed any more on the pear. It has not been possible so far to trace 
to what host the winged females migrate; by the middle of May the leaves of the 
pear not yielding any nutrient sap the insects desert them altogether. Empty 
pseudogalls contain only their exuviae and serve as hiding places for spiders and 
Coccinellids. 
The females (‘‘ spring migrants’’) that have flown off are rather delicate insects, 
smaller in size than the apterous viviparous females. . 
From May to December their history is obscure. In early December, or even 
before, alate females (‘‘ return migrants’) accompanied by alate males return to 
the pear or plum. The lower branches of the larger trees and the tops of open 
nursery plants are chosen for alighting. 
