GREGARIOUSNESS. 
123 
Himalayas, the remaining species are local. Scarcely any tiling can be 
said to be known of the family in India, their minute size and extreme 
delicacy being unfavourable to collection and preservation. 
The recorded species are :— 
Psocus longicornis. —F. 
Psocus nebulosus .—-St. 
Psocus taprobanes .—Hag. var. bengalensis. Kolbe. 
Psocus cinereus ,-—Enderl. 
Copostigma indicum .—Enderl. 
Ccecilius Inimalayanus .—Enderl. 
Amphipsocus pilosus. —Mack 
Ectopsocus denudatus .—Enderl. 
Myopsocus fraternus. —Hagen. 
Perientomum morosum. —Hagen. 
Lepium chrysochlorum End. —(Spol. Zeyl. 1906, p. 81). 
None are of the smallest economic importance though the insect 
eating one (Atropos sp.) is a great nuisance in the rains when specimens 
cannot be kept dry. The study of these insects, especially in the moister 
parts of India, would very greatly increase our knowledge of the group 
and yield valuable results from the biological, as from the systematic 
aspect. 
GREGARIOUSNESS 
If we exclude the purely social insects, in which for the good of the 
community there is a well marked division of labour accompanied by 
polymorphism, we find that the great mass of insects are, as far as we 
know, wholly solitary. Consider the commonest insects there are about 
us, and watch their ways ; all live for themselves individually and appear 
to take no notice of each other, except when impelled by the mating 
instinct. It is perhaps safe to say “ apparently 5 5 because for all we 
know there may be modes of inter-communication not revealed by 
external movements, as there must be certainly in some species of ants. 
There are, however, a small number of insects constantly gregarious, as 
apart from ‘ ‘ Social 5 5 and it is these forms we propose now to mention. 
The student will think of insects that migrate but these are gregarious 
only when this migrating instinct overtakes them and at other times are 
wholly solitary. 
