128 COLLECTION AND PRESERVATION OF INSECTS. 



and a crayfish ; spread them on a setting board, you will 

 find the extreme points, the tail, toes and antennae, display 

 the differences : so, in insects, take the extremities. The 

 extremities of an insect are the wings, the tarsi, the head ; 

 and these afford abundant characters. First, take the most 

 obvious parts, the parts most easily observed; then consult 

 the more concealed parts, as the mouth ; but even in the 

 mouth try the palpi before the jaw or the lip from which 

 they rise. 



In investigating insects, a good glass is a matter of great 

 importance ; and here I cannot resist the pleasure it will 

 give me most heartily to recommend Messrs. Bentley and 

 Chant, of King's Head Court, St. MartinVle-Grand. Being 

 themselves good entomologists, they know exactly what 

 entomologists require, and take every pains to supply it. 



The knowledge of the principal orders of insects is very 

 soon acquired ; many we have known from our childhood 

 upwards, as butterflies (Papilionites,) or crickets (Ache- 

 tites}. It is the safest plan to begin with large well-known 

 groups first ; the knowledge of a few of these leads us to 

 desire an acquaintance with the rest. 



After the orders are pretty well known, the study of spe- 

 cies must be begun ; for it is a remarkable fact, which the 

 author cannot explain, that classes, orders and species, 

 are much more readily ascertained, and much more obvious 

 to the casual observer, than the intermediate divisions of 

 stirpes, families and genera. It may also be observed, 

 that in general, even with scientific investigators, there is 

 less doubt as to the limits of classes, orders and species, 

 than those of the other divisions. Genera are the most 

 difficult groups to make out ; they depend almost entirely on 

 artificial characters, and their limits have never been agreed 

 on "by any two of the numerous writers on entomology. 



Most descriptions are written in Latin, or a language 



