TRACHEATA 355 
band which cuts into the thorax; they are sometimes orna- 
mented with bright metallic spots or patches. 
A few species, as Vanessa, hibernate, but most butterflies 
pass the winter in the larval or pupal state. The cycle of 
their developement does not extend over a year, but there may 
be two generations in a twelvemonth. 
The genus Papilio contains over 300 species; P. machaon 
is the swallow-tail. The family PrertDAE contains the numerous 
“whites.” Vanessa cardui is the “ painted lady,” and V. io the 
“peacock,” Apatura iris the “ purple emperor,” ete. 
OrpDER 5. COLEOPTERA. 
CHARACTERISTICS.—Jnsects with masticating mouth parts. The 
anterior wings are horny, and in some cases fused together. 
They do not overlap, but meet together in the middle line, 
forming a straight suture. The prothorax is moveable. The 
metamorphosis 1s complete. 
The order Coleoptera has received more attention at the 
hands of entomologists than any other order of Insects, and the 
number of species of beetles named and described far out- 
numbers that of any other group. The beetles form a fairly 
homogeneous assemblage ; and although they vary considerably 
in size and shape, they do so to a much less degree than the 
Orthoptera or Hemiptera. It is a comparatively easy matter 
to recognise a beetle. As a rule they are sombre in hue, but 
some of them show very beautiful metallic colours, especially 
after rain. ‘Their outline is usually oval, but it may be linear 
or almost round. 
The head is well developed, and may be free or partially 
hidden under the projecting prothorax; it bears antennae, which 
are usually two-jointed and of very various shapes. The antennae 
are in many cases different in the two sexes. With the excep- 
tion of a few blind species which inhabit dark caves, beetles 
usually have a pair of compound eyes; in the GYRINIDAE or 
whirligigs, which swim half immersed in the water, the eye is 
divided into two halves, one for seeing in the air and one for 
the water. Ocelli are as a rule absent. In the weevils and 
some allied families the head is elongated, and the mouth and 
