THE FOSSORIAL HYMENOPTERA. 
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with great dexterity. When they are adults their nourishment 
consists of fluids, such as the honey from flowers and the sap or 
gum of trees, but when they are larvae they are carnivorous, and 
can only exist upon living prey. Consequently the mothers are 
obliged to chase other insects, and to catch them for their larvae, 
and it is therefore a curious and suggestive sight to witness a non- 
carnivorous insect hunting prey for its carnivorous young, which 
it is never destined to see. There are only two kinds of in- 
dividuals amongst these Hymenoptera , namely, males and females, 
.and there are no special workers or neuters, as there are amongst 
wasps, bees, and ants. The females are always solitary, and work 
away at the building of their nests, and supply the young with 
food without any help whatever. Every female chooses an ap- 
propriate place, and each species has its particular fancies with 
regard to the future position of its young ; the locality may be 
chosen in the earth, a cliff, a wall, or in the stump of a bush. 
They often avail themselves of cavities formed by Nature, or of 
fissures and cracks, but the proper shaped hole is always formed 
with great energy and intelligence. The mandibles are the only 
instruments and tools, though the legs with their spines act as 
rakes to scrape out and eject the portions of earth detached with 
the jaws, but the industry and perseverance of the insects are so 
constant, and their patience is so wonderful, that a small gallery is 
soon dug out, and an oval shaped cell is made at the bottom 
of it ; sometimes several cells are excavated, but ever^ species has 
its peculiar arrangement as regards the number of the chambers. 
The chamber being formed, the Sphex , the Pompilus , the 
Crabro , or the Ody nevus , as the case may be, must immediately 
undertake to store up provisions within it, and therefore other 
insects are hunted, each species having its particular prey. Some 
like caterpillars, others the larvae of Coleoptera , and a few even 
attack spiders ; and the Sphex is gifted with that peculiar instinct 
which has already been noticed in the Ichneumons , for if it 
obtains a larva belonging to an insect which grows to a con- 
siderable size, it only places one in each chamber ; but if the 
larvae are small, several are introduced, ahd if they are minute 
it hunts down a crowd of them. When it seizes its prey, the 
fossorial Hymenoptera pricks it with its sting, the venom of 
