22 IMPERFECT SOCIETIES OF INSECTS. 
to them, emerging again in the spring: but in May and 
June they entirely desert them; and, losing all their 
love for society, live in solitude till they become pupe, 
which takes place in about a month. When they desert 
their nests, the spiders take possession of them; which 
has given rise to a prevalent though most absurd opinion, 
that they are the parents of these caterpillars*. 
With other caterpillars the association continues 
during the whole of the larva state. De Geer mentions 
one of the Zenthredinide of this description which form 
a common nidus by connecting leaves together with 
silken threads, each larva moreover spinning a tube of 
the same material for its own private apartment, in which 
it glides backwards and forwards upon its back>. I have 
observed similar nidi in this country; the insects that 
form them belong to the Fabrician genus Lyda. 
The most remarkable insects, however, that arrange 
under this class of imperfect associates, are those that 
observe a particular order of march. Though they 
move without beat of drum, they maintain as much 
regularity in their step as a file of soldiers. It is a most 
agreeable sight, says one of Nature’s most favoured 
admirers, Bonnet, to see several hundreds of the larvee 
of P. B. Neustria marching after each other, some in 
straight lines, others in curves of various inflection, re- 
sembling, from their fiery colour, a moving cord of gold 
stretched upon a silken ribband of the purest white; 
this ribband is the carpeted causeway that leads to their 
leafy pasture from their nest. Equally amusing is the 
progress of another moth, the Pityocampa, before no- 
Vol. I. 4th Ed. 477. Reaumur, ii, 125. > De Geer, ii, 1029, 
