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INTRODUCTION TO ENTOMOLOGY. 
“On reconnaitra partout l’empreinte de cette Intelligence 
adorable, qui crayonna, de la meme main, l’Homme et la 
Mouche.” — Bonnet, Contemp. de la Nature. 
Insects form a portion of that extensive department 
of animated nature known by the name of Articulated 
animals. They are so called on account of being 
composed of joints or segments, a structure which 
renders their bodies pliant, and thus compensates 
for one of the inconveniences that would otherwise 
arise from the want of a vertebral column. Some 
ancient authors designated them by the term annulata 
- — quasi in annulos secta — and they are frequently de- 
scribed in modern works as annulose animals. They 
are now referred to five great classes : 1. Annelides, 
such as leeches and earthworms ; 2. Crustacea , such 
as lobsters and crabs ,* 3. Arachnides , such as spiders 
and scorpions ; 4. Myriapodes , consisting of juli and 
scolopcndrse ; 5. Insecta , containing beetles, butter- 
flies, &c. 
The term insect has likewise been suggested by 
the structural peculiarity just alluded to, the trans- 
verse divisions causing the body to appear intersected 
or cut into ; and the Latin word insectum, from 
