Instructions for collecting Insects. 2 1 3 



Art. II. — Instructions for the benefit of those, who are engaged in < 

 lecting Insects for cabinets of Natural History; by M. Theodc 

 Roger. Translated for the American Journal of Science, ft 



Li 



first volume of the Bulletin d'Histoire Naturelle 



General Rules 



The object of an entomologist being to become acquainted with 

 all the species of insects, that may exist, it is necessary that he should 

 be on his guard against the prejudice, that very naturally leads one 

 to consider as the most valuable the insect, that is of a large and 

 singular form and brilliant color. 



The mountains nourish insects, the greater part of which differ 

 from those of the surrounding plains. Soils of a different nature 

 produce likewise different species. Whoever, therefore, would col- 

 lect the greatest possible number of insects in a country, must be 

 at the pains of exploring, for this purpose, all situations from the 

 most arid, to those, that are covered with the richest vegetation. It 

 is, however, to be observed, that in these last he will find a far greater 

 number of species, and, in general, these species are far more abun- 

 dant. To these places it will, therefore, be necessary to direct bis re- 

 searches the oftener. 



The manners and habits of insects are also very various. Some 

 adhere to flowers ; others live on the trunks of trees, or under their 

 bark, more particularly, the bark of old trees, that are decayed and 

 rotten ; certain species are found on stones, and in the earth at the 

 foot of trees, especially in moist places, that border on rivulets and 

 stagnant waters. 



There are, besides, multitudes, that live in manure, in mold, in 

 rubbish, and in the remains of vegetables and animals in a state of 

 putrefaction ; some species live in mushrooms ; finally, stagnant wa- 

 ters nourish them in very great numbers. 



Insects are generally so fragile that they are very easily injured 

 when taken. Nevertheless, in order to facilitate their classification 

 in a collection, it is indispensable that they should be entire, and that 

 their colors should not be effaced ; for the characters, that serve to 

 assign them their place, are always derived from the form of their 

 claws, that of their feelers, the number of articulations in their tarsi, 



V-ol. XIX.— No. 2. 28 



