CH. I.] PARALYZED CATERPILLARS. 147 
power, by stinging it is supposed—though I be- 
lieve that some of these insects never use their 
stings for purposes of defence—of partially dead- 
ening (though without destroying) the vital prin- 
ciple of insects stored up as food for their young. 
I much regretted being unable to watch the pro- 
gress of this interesting piece of domestic eco- 
nomy. 
Although this insect exactly resembled the 
Odynerus parietinus, yet I hesitate to express a 
positive opinion that it was. of that species, as the 
Parietinus appears—so far as the knowledge at 
present possessed of its habits extends—to provide 
for its young a number of small caterpillars, in- 
stead of one large one for each as in the present 
instance. That it may, however, thus adapt itself 
to circumstances in the selection of the food to 
be stored up, is at least possible ; and the fact, if 
ascertained, would only add another to the num- 
berless instances in which the marvellous instinct 
of insects is displayed’. 
1 This method of providing food for their young is not 
confined to the Mason Wasps—it being adopted also by the 
Sphegide, Pompilide, and others—and appears to prevail very 
widely throughout the world. Darwin, in his interesting Va- 
turalist’s Voyage round the World, mentions the same thing 
as happening, under very similar circumstances, at Rio de 
L2 
