INSECTA. 80t 



All these as well as the scorpion, are produced perfect from the 

 parent, or the egg; and to undergo no changes after their first exclusion. 

 They are seen of all sizes ; and this is a sufficient inducement to suppose 

 that they preserve tlieir first appearance through their whole existence. It 

 is probable, however, that, like most of this class, they often change their 

 skins; but of this Ave have no certain information- 



CLASb: IX. — INSECTA. 



Articulated animals with six ie-fs, respiring by means of trachea ; head distinct 

 from the thorax ; two antenncz. 



This branch of science named Entomology, (from EPiofiov, an insect, and 

 i.oyo;, 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 he 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, i ^ 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 Insecta is derived from the Latin m, into, and seco, I cut, frora 

 the body having the appearance of being cut or divided into segments; and 

 a term of the same meaning, eviofia, {er and xf/ii'w,) was used by the 

 Greeks. 



Linnaeus, 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 Linnssus founded his arrangement, were 

 chiefly the wings, and hence his system has been called the alary system. 

 The class Insecta, of Linnseus, however, as it stands in the twelfth edition 

 of his Systema Naturcp, included the Crustacea and arachnides. He divides 

 the whole into seven orders, viz. 



I. CoLEOPTERA, (from y.oleog, a sheath, and 7tTeQbv,a tving.) Wings fouFj, 



the upper ones crustaceous, with a straight suture. 

 II. Hemiptera, (from Tj.aiffu, half, and mEQov.) Winga four, semicrusta- 



ceous, incumbent, 

 ni. Lepidoptera, (from IbuIc, a scale, and nTeqbv.) Wings covered with 



imbricated scales. 

 IV. Neuroptera, (from vIvqov, a chord or string, and nieqhv.) Winga 

 membranous, with ribs or nerves ; anus unarmed. 

 101 



