FOSSOBIAL HYMENOPTEBA 
441 
(vide Frontispiece, Fig. 4, Synagris negusi, and photo No. 1). 
this is not the case in Fossors. As regards habits, true wasps 
are often — indeed, are supposed popularly to be always — social, 
while each Fossor lives entirely an independent life ; although, 
if conditions favour, a number may nest in the same small area, 
so that in this way they are gregarious. Many true wasps, 
however, live similar independent lives, and are closely allied 
in their habits to some of the Fossors. 1 What, then, are the 
habits which are so important as to give the group its name ? 
The Fossors have brought to a highly specialised standard 
a habit which is, primarily, quite simple — namely; the feeding 
of their young with other insects. The common wasp at home 
may often be noticed to pounce on a fly, cut off its wings 
and legs, reduce the body to a mangled pulp, and carry it off 
— to feed upon ? No ; the adult feeds purely from flowers 
or on honey stolen from more conscientious workers : the 
mincemeat is for the brood of young in her parchment 
nest underground. 
A wasp which is very well known out here, Belonogaster 
griseus, F., by name (vide Frontispiece, Fig. 2, Belonogaster 
griseus), has added something to this simple method. This 
is the much- disliked, dark-brown wasp, with very thin pedicle 
to the abdomen ; it constructs parchment nests, hanging 
from a narrow stalk, in the cells of which, open at the bottom, 
its larvae are suspended head downwards. (Photos Nos. 2 
and 3.) 
Out in the field, one often comes across one of these wasps 
hunting, and may perhaps witness her discovery of a suitable 
caterpillar. She stings it — often in several places seriatim — and 
then proceeds with her mandibles to reduce the helpless insect 
to pulp, which she forms into a round ball and carries back 
to the nest, where other nurses assist in distributing it to the 
larvae. Here is a distinct advance ; the prey being large 
might be rather obstreperous under the process of pulping, 
and is rendered helpless by a preliminary stinging. 
This method, however, involves continual supplies of 
fresh-killed meat and careful attention throughout the whole 
life of the larva. The next step above the somewhat crude 
1 Compare Odynerus with Sceliphron. 
