THE MUTILLA. 
215 
apart, but it provisions them all in the same manner, and deposits 
a single egg in each ; then its work is done, and it soon dies. 
Thus this mother has taken infinite pains, has shown a wonderful 
foresight, and has laboured without rest for the sake of a progeny 
which it never can see, and which has habits totally unlike its own. 
This is the result of instinct, whatever that may be, and it is 
evidently not the result of reason. Some interesting details bearing 
upon this subject will be noticed further on, when Bembex vidua 
is described. 
There are some species in all the families of nest-making 
insects which have the usual organisation and the same method of 
development, but which have no structures with which they can 
labour, and which have no maternal instincts for the benefit of 
the larvae. We have noticed that some ants make slaves of the 
individuals of other species who can render proper assistance to 
the young, and do such work of which they themselves are 
incapable ; and amongst the fossorial Hymencptera some may be 
found which cannot chase prey and enclose it in cells, but they 
manage to introduce their eggs into the galleries and nests which 
have been well furnished with victims by hunting Hymenoptera. 
Thus the females which cannot hunt manage that their larvae 
live like comrades at the expense of those of the fierce and in- 
dustrious kinds. They introduce their eggs, and the larvae are soon 
hatched, and crawl out of the egg sooner than those to whom 
the nest really belongs ; the consequence is, these parasites — the 
offspring of lazy parents — eat up a large portion of the provisions 
laid up in store, to the great detriment of the others. The female 
Hymenoptera which act in this very human manner have neither 
mandibles proper to excavate earth, nor legs so spined that they 
can act as rakes ; so not having a mechanical power, they use 
their wits at the expense of the goods of those insects which 
are endowed with the means of labouring. 
The MiUillidce were formerly taken for ants, because the 
females, having no wings, can only run over the ground, and 
thus resemble the neuter or worker ants. They are solitary 
insects, and consist only of males and females, the former having 
wings. They are found in all parts of the globe, and principally 
in the tropics. The genus Mutilla is found in Europe and in 
