THE COLEOPTERA. 
265 
unusually interesting about them ; but this is not the case. The 
Coleoptera have no industrial occupations, and their instincts are' 
very limited. In examining into their physiology we do not find 
any of those remarkable gifts and instincts, almost amounting to 
reason, that characterise the Hymenoptera , and which are amongst 
the most instructive and wonderful phenomena of Nature. It 
would appear that the charms of the Coleoptera , and the interest 
that they have excited amongst naturalists and collectors, are 
referable to the beauty of some of them, and to the ease with 
which they may be preserved, in consequence of the density of 
their structures and the nature of their wings. There is no diffi- 
culty in distinguishing any one of the beetles from all other 
insects. The most distinctive character is in the wings, which, 
so far as the beetles are concerned, are four in number, and in 
two pairs. The fore wings are always of the same hard coria- 
ceous texture as the other parts of the body ; they never cross 
one over the other when the insect is at rest, and they cover 
the body more or less perfectly. They are sheaths, and act as 
coverings to the hind pair. The name Coleoptera is taken from 
this peculiarity (/coXeo?, sheath ; 7 rrepa, wings), and the sheaths 
are usually called “ elytra.” These elytra, when the insect is at 
rest, are joined to each other at their inner margins, and thus 
form a sort of middle line upon the top of the body. They open 
at right angles with the body and project straight out from it, 
and remain fixed in that position when the beetle is flying, and 
they do not beat the air or vibrate so as to produce motion. The 
hind wings, which are almost always much larger than the fore 
wings, are membranous, and are marked with many branching 
nervures, and these wings, when the insect has done flying, fold 
themselves up and are hidden underneath the elytra. The mem- 
branous wings are strongly vibrated during flight, and do not 
remain at right angles to the body like the others. The structures 
of the mouth are usually well developed and strong, and are 
fashioned for the purposes of mastication. 
The Coleoptera undergo complete metamorphoses. They are 
born as larvae, like the Lepidoptera and the Hymenoptera , and 
the larvae are transformed into immovable or quiet nymphs, which 
are, like those of the Hymenoptera , the exact casts or models 
