ORDER III. LEPIDOPTERA. 309 



The hemiptera comprise some of the most noxious as 

 well as the most valuable kinds of insects. The devasta- 

 tions occasioned by locusts, are too well known to be 

 enlarged on here. The most luxuriant face of nature 

 they turn into a desolate wilderness. When these insects 

 take the field, they appear to be under the conduct of a 

 leader ; whose flight they observe, and direct their motions 

 accordingly. At a distance they resemble a black cloud ; 

 which, as it approaches, gathers on the horizon, and 

 threatens to obscure the light of the sun. It often happens 

 that the husbandman perceives this impending storm pass 

 away ; and the whole swarm proceed on their course to de- 

 vour the labours of some devoted country. Unfortunate 

 indeed is that district where these multitudes alight ! In a 

 few minutes they desolate the promise of the year, and 

 often bring on all the horrors of famine. The inhabitants 

 of some countries, however, convert this plague into a 

 real benefit : for, in many kingdoms of the East, and in 

 some parts of Africa, locusts are pursued as an article of 

 wholesome and not disagreeable food, when properly 

 dressed. 



The coccus genus also furnishes some estimable drugs, 

 and auxiliaries to the arts. The cochineal, the kermes, 

 and the gum-lac, are all produced from its different 

 species. 



ORDER III LEPIDOPTERA. 



INSECTS of this order have four wings, all of them im- 

 bricated with scales. It comprises the beautiful tribes of 

 moths and butterflies: the former distinguished by having 

 filiform feelers, and flying chiefly by night ; the latter by 

 the clavated feelers, and by pursuing the business of their 

 lives in the day time. These insects, so attractive by the 

 elegance of their forms, and the vivid lustre and variety of 



