158 
E. M. CAMPBELL-OLE SOCIAL WASPS. 
an inch in length, and so strong is its attachment that the larva 
when hatched can sway to and fro, shrink into a sphere, or extend 
itself to full length without leaving the cell, and without running 
any risk of falling. It now becomes dependent on the workers for 
its daily food, which is sometimes given in the form of small pieces 
of insects, and at others as a liquid regurgitated from the pouch of 
the nurse, just as the honey-bee deposits the honey it has collected. 
The larvae have strong mandibles in all their stages, and it is a 
pretty sight to see them, when disturbed by some movement, stretch 
themselves out to their full length, and open and shut their mandi¬ 
bles with as much unmistakable expression of a desire for food as 
the fledglings in a bird’s nest. They are easily fed. I was a 
foster-mother to about a hundred for nearly a fortnight this year, 
and the avidity with which they partook of all kinds of animal 
food showed the great quantity of insect-life required to support 
the inmates of a single wasp’s nest. The larvae remain attached by 
the tail to their egg-shell until after they have shed their first skin; 
and now commences the first important epoch of a wasp’s life. 
Let us bear in mind that a larva in this stage is hanging obliquely 
from a spot about half-way up its cell, which opens downwards, 
and before it turns into a cocoon it has to abandon its old anchorage 
and find another at the top of its cell. Many seem to fail in this 
attempt, and fall, when they are removed from the nest, possibly 
for the same reason that the sick and weakly babies are destroyed 
by some savage races. 
But the question remains to be answered: How is it that any 
larvse manage to perform unassisted this acrobatic feat ? The larva 
has no legs, but it has strong mandibles; while at the end of the 
abdomen there is a surface on which are two protuberances. 
"When these are withdrawn, the surface forms a sucker which can 
be released by their protrusion. It is possibly by the alternate 
attachment of the mandibles and the sucker to the different sides 
of the cell that the larva accomplishes its first journey, which 
would be after the manner of the now superseded sweep-boy up 
a chimney. 
The larva having reached the top of its cell secures itself by 
its sucker, feeds, if possible, more voraciously, and commences to 
spin its cocoon, or the silken tube which is to protect it during 
its pupa stage. A delay in this work would be fatal to the 
perfect development of the insect, for the larva soon becomes 
so fat that it is impossible for it to turn and reach the bottom of 
its cell with its mouth, where the glands yielding the secretion 
which forms the threads are situated. The time now soon arrives 
when the larva entirely fills its cell, and begins to cover the 
opening with a silken texture. Unlike the larva of the bee, which 
is assisted by its elder sisters, who place on the top of the cells a 
thin wax covering, the wasp’s larva, with a spirit of independence 
such as might be expected from the offspring of a predaceous 
insect, performs all the work of the cocoon by itself. Self- 
imprisoned, it casts its second skin, and in a little more than three 
