45 
of Cerceris, Smith observed C. arenaria carrying to its nest Curculionidee of 
very diverse forms, while C. labiata used a beetle—J//altica tabida—of the 
family Chrysomelidie. 
The beetles, after being caught, are stung in the chief articulation of the body, 
that, namely, between the pro- and meso-thorax. Cerceris bupresticida con- 
fines itself exclusively to beetles of the family Buprestidze. It was by observa- 
tions on this insect that Dufour first discovered the fact that the insects stored 
up do not decay; he thought, however, that this was due to the liquid injected 
by the wasp exercising some antiseptic power; but the observations of Fabre 
have shown that the preservation in a fresh state is due to life not being extin- 
guished; the stillness, almost as if of death, being due to the destruction of the 
functional activity of the nerve centers that govern the movements of the limbs.¢ 
Between the habits of such wasps and those of the keleps the dif- 
ferences are certainly less than between the keleps and the true ants, 
and another wasp of the same family shows how the transition from 
the parasitic to the predaceous stage could be passed very gradually. 
Instead of concluding its maternal duties by stocking its nest or bur- 
row with paralyzed insects in advance, Philanthus apivorus, which 
preys upon the domestic honeybee, provides only one individual at 
first and returns later to bring others, as required by the growing 
larve. Moreover, it has the habit of crushing its prey in its mandi- 
bles, thus giving the larva easier access.’ The kelep system repre- 
sents a further improvement, the captured weevils being pulled to 
pieces and distributed to numerous larve. In one group of Hymen- 
optera, the sawflies, the larvae have well-developed legs and are able 
to crawl about like caterpillars, which they very much resemble. In 
all the other families the larve are legless, helpless grubs. Most of 
them are, in the larval stage, parasites, either of plants or of animals. 
Those which are not parasitic require, obviously, to be fed and cared 
for by their mothers, a condition most conducive, obviously, to the 
development of social habits. 
The distinction between predaceous and parasitic habits is not 
easy to draw. Mrs. Cook saw three young kelep larve at one time 
attached to a termite which the workers were still carrying about to 
feed to the larger larvee, which seem to secure nearly all of the direct 
attention of the workers. If the prey remained alive such attached 
larvee would be looked upon as parasites. 
The manner in which the keleps feed their prey to their larve is 
thus to be looked upon as a derived rather than as a primitive trait, 
compared with the habits of the other carnivorous Hymenoptera. 
«Sharp, David, 1901, Cambridge Nat. Hist., Insects, 2 :125. 
5 There are two other significant approximations of habits between the kelep 
and these wasps of the family Philanthidze. They seize their prey in their 
mandibles and sting it by bending the body around underneath, to reach the 
vulnerable point. Philanthus also makes long burrows in the ground, with 
chambers at the end in which the eggs are laid and the young reared. 
