442 
DISCURSIVE NOTES ON THE 
process of the true wasps is perhaps exemplified by Fossors 
of the family Bembecidce, which, as was said, merit more than 
most the title ‘ sand-wasps.’ These, so far as my experience 
goes, only burrow in sandy places ; the reason being that they 
have not yet got beyond the stage of a frequent supply of 
fresh meat to their young. As the burrow needs to be con- 
stantly reopened, the labour would be very great were it not 
in some light, easily displaced, soil ; hence loose sand is chosen. 
The reason why these Fossors bring daily supplies to their 
young is perhaps the nature of the prey : two-winged flies 
are not fleshy insects, and if stored up in number sufficient 
for the food of the larva until it has finished growing would 
probably dry up. 
Bo the Bembecid hunts flies daily, stings each one, and 
brings it back, whole, to the larva at the bottom of the burrow. 
I am not quite certain, from memory, whether the Fossor 
really kills the fly, or only paralyses it, but believe the latter 
is the case. This method is a distinct advance upon the last 
mentioned, but still involves frequent reopening of the burrows 
to introduce fresh supplies. Two other well-known families 
of Fossors — Sphegidce and Pompilidce — provide once and for 
all for each larva, by storing up at the bottom of the burrow 
a supply, according to size, of one or more insects or spiders 
which have been stung, so that they are paralysed and probably 
insensitive, but are still alive ( vide photo No. 4). The helpless 
Fossor larva thus has live meat in a defenceless condition, 
and feeds first on the juices and fats only, leaving the vital 
parts until the end when all save skin is consumed. 
A mother Sphegid or Pompilid, having dug her burrow, 
found her prey, stung it, brought it back to the burrow, laid 
an egg on it, and filled up the burrow, has fulfilled her duty 
to that egg, and sets to work to provide for another. This 
method, however, still has its limitations, imposing heavy 
labour upon the mother ; and another family of Fossors, the 
Scoliidce ( vide Frontispiece, Fig. 8, Scolia ruficornis), seems to 
have gone one better. Instead of laboriously excavating a 
burrow the mother Scoliid searches out the destined prey of 
her young in its own burrow. 
This is commonly the fat larva of large Lamellicorn beetles, 
