SYSTEM OF NATURE. 
103 
Necromorpha ; 
In which the penultimate state is provided with mouth and 
organs of locomotion, detached from the body, but so en¬ 
veloped in a case that it can employ neither. The resem¬ 
blance therefore to the perfect insect is very considerable, 
except in the total want of motion. This group contains 
two classes of insects. 
Class III.— Hymenoptera ; in which the perfect insect 
has four fully developed wings, all of them transpa¬ 
rent or membranous, and without scales. 
Class IV. — Coleoptera ; in which the perfect insect 
has two fully developed wings, and two wing-cases 
which cover the wings. 
ISOMORPHA ; 
In which all the states are active and voracious, and of 
similar form. This group contains two classes of insects. 
Class V. — Orthoptera ; in which the perfect insect 
has four wings, the first pair being leathery, of little 
use in flight, and often very minute and scarcely 
apparent: the mouth is furnished with two strong 
mandibles, meeting transversely. 
Class VI. — Hemiptera ; in which the perfect insect 
has four wings, a portion of the first pair often being 
leathery : the mouth is a tubular sucker, formed for 
extracting the sap of plants. 
Anisomorpha ; . 
In which the amorphous, necromorphous and isomorphous 
characters appear, together with others not possessed by 
those groups. This group contains but one class of insects. 
Class VII. — Neuroptera ; in which the perfect insect 
has four reticulated wings. 
