CLASSIFICATION OF INSECTS. 117 



SUB-CLASS B. 



The small remaining section, consisting of Insects which un- 

 dergo no metamorphosis, and are destitute of wings, includes 

 two orders. 



Order X. ANOPLOURA (Louse). These are distinguished from 

 the succeeding, by the absence of appendages to the abdomen. 



Order XI. THYSANOURA (Spring-tails, fyc.) In these the 

 abdomen is furnished with false legs, or appendages, adapted for 

 leaping. 



Besides these principal groups, there are some small interme- 

 diate orders, by which the former are connected. These are not 

 admitted, however, by all Entomologists. Thus the Earwig 

 tribe, which combines, in some degree, the characters of the 

 Coleoptera and Orthoptera, is raised by many to the rank of a 

 distinct order DERMAPTERA, which leads from the first to the 

 second order. Again, a separate order TRICHOPTERA, has 

 been formed to include the Caddice-flies, which are intermediate 

 between the Lepidoptera and Neuroptera. And, lastly, there is 

 a small order STREPSIPTERA, or RHIPIPTERA, which includes a 

 small group termed Wasp-flies, intermediate, in several respects, 

 between the Hymenoptera and Diptera, but differing from both 

 in so many particulars, as apparently to require being arranged 

 by themselves. 



ORDER I. COLEOPTERA, OR BEETLES. 



638. The insects composing this Order, all of which are known 

 under the common name of Beetles, are the most numerous and 

 best known of the whole class. The singular forms and brilliant 

 colours exhibited by many of the species, the size of their bodies, 

 the solid texture of their integuments, which facilitates their 

 preservation, and the nature of their habits, which makes 

 their capture more easy, have combined to render them an ob- 

 ject of peculiar attention to Entomologists, many of whom have 

 devoted themselves to this order exclusively. It is probable 

 that from 30,000 to 40,000 species of Beetles alone now exist in 



