INSECTA. Bul 
All these as well as the scorpion, are produced perfect from the 
parent, or the egg; and to undergo no changes after their first expulsion 
They are seen of all sizes; and this isa sufficient inducement to suppose 
that they preserve their first appearance through their whole existence. It 
1s probable, however, that, like most of this class, they often change their 
skins; but of this we have no certain information. 
CLASS IX.—INSECTA. 
Articulated animals with six legs, respiring by means of trachee ; head distinet 
from the thorax ; two antenne. 
Tus branch of science named Entomology, (from &toseor, an insect, and 
Aoyos, discourse,) including the most numerous class of organized beings, 
has but lately risen into merited consequence. The use of insects, indeed, 
in the economy of nature, was not likely to be estimated by men in the in- 
fancy of society, to whose wants or conveniences they were apparently little 
calculated to afford any addition. To some tribes, however, attention must 
have been early directed, « 1 account of the ravages their united myriads 
enabled them to perpetrate ; and others were early noticed as the industrious 
collectors of a species of food which man has long converted to his use. 
The term Jnsecta is derived from the Latin zn, into, and seco, I cut, from 
the body having the appearance of being cut or divided into segments; and 
a term of the same meaning, evroua, (ev and teurw,) was used by the 
Greeks. 
Linneus, whose powerful genius enabled him, in this, as in other branches 
of natural history, laid the foundation or arrangements, from which all that 
has since been done has emanated. 
The characters upon which Linneus founded his arrangement, were 
chiefly the wings, and hence his system has been called the alary system. 
The class Insecta, of Linneus, however, as it stands in the twelfth edition 
of his Systema Nature, included the crustacea and arachnides. He div:des 
the whole into seven orders, viz. 
I, Corzorrera, (from xodedc, a sheath, and mtegdv, a wing.) Wings four, 
the upper ones crustaceous, with a straight suture. 
II. Hemierera, (from juwov, half, and mtegdv.) Wings four, semicrusta- 
ceous, incumbent. 
III. Lerworrera, (from dents, a scale, and mtegdv.) Wings covered with 
imbricated scales. 
IV. Nevrorrera, (from vévgor, a chord or string, and 7tegdy.) Wings 
membranous, with ribs or nerves; anus unarmed. 
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