564? INVESTIGATION OF INSECTS. 



the Dynastida and many other Petalocerous beetles, the 

 principal specific character is derived from the horns or 

 tubercles that arm the head and thorax : in Lucanus 

 from the mandibulcs : and in Prionus from the marginal 

 teeth of the thorax. If the insect, then, you want to 

 name belongs to any of these genera, having observed 

 its peculiar characters in this respect, you may ascertain 

 in a very few minutes whether any already described 

 exhibit the same. This facility of investigation can be 

 better acquired by practice than precept, and cannot be 

 attained all at once. The above hints, however, may be 

 of some use ; and cannot fail to be so, if you always en- 

 deavour to make yourself acquainted by a previous care- 

 ful examination with the characters of every new insect 

 you acquire, whether those of form, colour, or sculp- 

 ture, before you attempt to discover its name in Fabri- 

 cius or any other author. 



When you have made such proficiency in the study 

 as to be familiar with a few species of each section of an 

 extensive genus, the labour of investigation will some- 

 times be greatly facilitated by attending to that con- 

 formity between the proportions, general aspect, and 

 figure of a known and an unknown insect, which Natu- 

 ralists express by the name of habit, and which, though 

 easily perceived by a practised eye, is described with 

 such difficulty. Scientific Entomologists in their de- 

 scriptions have usually taken care to place near to each 

 other, species agreeing in habit. When therefore you 

 know the name of one species, and find another of the 

 same general habit, you may commonly take it for 

 granted that if described at all by your author, it will be 

 placed near that already known to you. Thus, suppo- 



