INDIRECT BENEFITS DERIVED FROM INSECTS. 255 



and are scattered by the winds, while the grass upon 

 which it rested, no longer smothered by an impenetrable 

 mass, springs up with increased vigour. 



Numerous are the tribes of insects to which this office 

 is assigned, though chiefly if not entirely selected from 

 the two orders Coleoptera and Diptera. A large propor- 

 tion of the genera formed, by different authors, from 

 Scarab&us of Linne, viz. Scarabteus, Copris, Ateuchus, 

 Sisyphus, Onitis, Onthophagus, Aphodius, and Psammo- 

 dius ; also Hister, Sphaeridium , and amongst the Bra- 

 chyptera, the majority of the Staphylinidce, many Aleo- 

 char<z, especially of Gravenhorst's third family, many 

 Oxytelismd. some Omalia, Tachini and Tachypori, of that 

 author, including in the whole many hundred species of 

 beetles unite their labours to effect this useful purpose : 

 and what is remarkable, though they all work their way 

 in these filthy masses, and at first can have no paths, yet 

 their bodies are never soiled by the ordure they inhabit. 

 Many of these insects content themselves with burrowing 

 in the dung alone ; but Ateuchus pilularius a , a species 

 called in America the Tumble-dung, whose singular ma- 

 noeuvres I shall subsequently have to advert to, Copris 



a The Coprion, Cantharus t and Heliocantharus of the ancients was 

 evidently this beetle, or one nearly related to it, which is described 

 as rolling backwards large masses of dung, and attracted such general 

 attention as to give rise to the proverb Cantharus pilulam. It should 

 seem from the name, derived from a word signifying an ass, that the 

 Grecian beetle made its pills of asses' dung; and this is confirmed by 

 a passage in one of the plays of Aristophanes, the Irene, where a 

 beetle of this kind is introduced, on which one of the characters 

 rides to heaven to petition Jupiter for peace. The play begins with 

 one domestic desiring another to feed the Cantharus with some bread, 

 who afterwards orders his companion to give him another kind of 

 bread made of asses' dung. 



