1918. | BASHAMBAR DAS : The Aphididae of Lahore. 233 
Goot (1913) into three more new genera with differences of rather minor importance, 
such as the partial or total absence of lateral tubercles. These he has named Semi- 
_aplus for À. carotae (Koch), Brachysiphum for A. thalictri (Koch), and Longicaudus 
for Hyalopetrus trirhodus (Walker), etc. 
The Peganum Aphid departs materially from the definitions furnished for these 
genera, particularly in the structure of the antennae. What is now regarded by 
modern writers as the sixth joint consists of two parts, the proximal known as the 
‘‘ base ’” and the distal, which is often filamentous, as the “‘spur,’’ “unguis’’ or 
‘processus terminalis.” The latter when longer than the former was counted by the 
earlier authors as the seventh joint and two main divisions were recognised, one with 
six-jointed and the other with sevea-jointed antennae. Lachnus and Aphis were 
representatives of these groups according to Passerini, Buckton, Lichtenstein and 
others. This has been shown to be an incorrect view, and the family Aphididae was 
split up into a larger number of more natural groups by Mordwilko (1908), who has 
been mainly followed by van der Goot (1913). | 
The “harmal’’ Aphid evidently belongs to their ‘‘ Aphidina’’ tribe, but none 
of the genera comprised in it possess an antennal spur shorter than the base of the 
sixth article. I have thought it advisable, therefore, to place it in a new genus, 
Brachyunguis. Other distinctive features, besides, are the small cornicles, much 
longer cauda and the presence of lateral tubercles on the abdomen. Two more 
species belonging to this genus have been collected in Lahore. 
Life-history.—The harmal plant usually perennates by means of an underground 
root-stock, when the portion above the soil dies out after the flowering period is over. 
This takes place twice a year. New shoots arise about February and, after flowering 
in March and April, die off in May or June. The same rhizome sprouts again after 
the rains, beginning from September and continuing up to about December, when 
again only dry branches are to be seen. So the periods of growth during the year are 
roughly in spring and autumn. 
The Peganum Aphid has adapted itself remarkably to this periodicity in the 
growth of itshost. The eggs laid in December hatch in February or March. The stem- 
mothers vigorously carry on parthenogenetic reproduction and one finds whole 
branches lined from top to bottom with rows of concolorous individuals. Alate and 
apterous forms are given birth to promiscuously until about the middle of April or 
early May, when some sexual individuals are formed. ‘These are not very common, 
as only a few were observed in the colony. After the fruiting period is over there is 
very little sap left in the branches and the heat too becomes intolerable. The para- 
sites of this Aphid also breed very quickly, the Coccinellids and Syrphids completing 
their life-histories in shorter intervals of time. 
Almost all the Aphids are therefore destroyed, except those that have crept under- 
ground to take shelter in moist cool places. None are to be observed above the soil. 
Some eggs are at this time deposited on the plants by oviparous females. These 
eggs must hatch in September, when the hottest part of the year is over and the 
plants are reviving. It is also possible that some individuals creep out as apterous 
