CLASSIFICATION. 
In order to avoid the necessity of reference to other 1 ! entomological 
works, and to assist as far as possible those who are not familiar with 
'he divisions of the insect class into orders, families, etc., I will add 
here the characters of the order, sub-order, etc., to which these insects 
[Delong. By reference to my first report the position of this order in 
;he class will be seen. 
ORDER HK M^PTERA. 
The insects of this order are distinguished from those of other or- 
lers by the following characteristics: 
1st, Bj the .mouth, which is formed for sucking by being prolonged 
nto a slender, horny, jointed tube, which is usually bent under the 
)reast when not in use. 
2d. By the fact that they do not undergo a complete transforma- 
ion or change as do the beetles and butterflies (which are at first 
Tubs or caterpillars, and then quiet chrysalids taking no food), the 
arvae and pupae being similar in form to the perfect insects, the lat¬ 
er not quiescent, but active and taking food as the larvae and perfect 
nsects. 
These characters include a very large number of insects, many of 
rhich differ very widely from each other in several important respects, 
^he Order has therefore been divided by certain prominent characters 
n two Sub-Orders (by some treated as Orders), as follows: 
Sub-Order Heteroptera. —Wings, when present, four; the front 
'air larger than the posterior pair; lapping over each other at the tips, 
he basal portion thickened and leathery, while the portion at the tip 
! is thin and membranous. The body is usually flat- 
tened above, and the wings, when at rest, always lie 
flat upon the abdomen. The mouth or beak arises 
from the front of the lower part of the head. Fig. 
1 shows an example of this sub-order; a is the beak 
/l|r\ enlarged; b , the insect. This sub-order contains the 
b squash-bug, chinch-bug, bed-bug, tarnished plant-bug, 
Fig. i. water-measurers, water-boatmen, etc. 
Sub-Order IIomoptera.— Wings, when present, four, (except in the 
ark-lice, where there are but two); the front pair usually .slightly 
irger than the posterior pair; entirely membranous, sometimes slightly 
lickened, sometimes thin and transparent, but always similar in char¬ 
ter'throughout and not differing in character at the base from the 
p. When at rest (with few exceptions) the wings rest against each 
i • 
