INSECTS. 
17 
minute scales, of various shapes and sizes on the 
different species, and even on the different parts 
of the same animal. Their general appearance 
is more or less fan-shaped, and they are disposed 
in the manner of tiles on a roof, lapping over each 
other. 
The fourth order is called Neuroptera, or nerve- 
winged. The insects of this order are remarkable 
for the reticulated appearance of the wings, the 
fibres running into ramifications and decussations 
over the whole surface. This order is exemplified 
in the Libellulm or Dragon-Flies, &c. in which 
this character is remarkably conspicuous: the 
wings are always four in number. 
The fifth order is called Flymenoptera, and con- 
sists of insects furnished with four membranaceous 
wings, and also with a sting, or a process resem- 
bling one. It is exemplified in the well-known in- 
sects of the Bee and Wasp tribe and many otheTs. 
The sixth o-rder is entitled Dipferdy and contains 
such insects as are furnished with two wings only. 
In this order rank Flies, strictly so called, as well 
as Gnats, and a great variety of other insects. 
The seventh and last order is termed Apterdy 
and consists of such insects as are totally destitute 
of wings, as Spiders, Centipedes or Scolopendras, 
Fleas, and many others. To this order also belong 
the numerous species of the Crab and Lobster 
tribe, which by some naturalists are excluded from 
the class of Insects. It may be here observed, in 
order to prevent mistakes, that some of the Cole- 
opterous Insects are destitute of wings, having 
V. VI. p. I. 2 
