216 INDIEECT BENEFITS DEKIVED EROM INSECTS. 



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 proportion of the 

 genera formed, by different authors, from ScarabcRus of Linne, 

 viz. Scarahceus, Copris, Ateuchus, Sisyphus, Onitis, Ontho- 

 phagus, Aphodius, and Psammodius ; also Ulster, Sphceri- 

 dium ; and amongst the Brachyptera, the majority of the 

 Stapliylinidce, many Aleocharce, especially of Gravenhorst's 

 third family, many Oxyteli, and some Omalia, Tachini, and 

 Tacliypori, 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 

 species called in America the Tumble-dung, whose singular 

 manoeuvres I shall subsequently have to advert to, Copris 

 lunaris, Geotrupes stercorarius, and many other lamellicorn 

 beetles, make large cylindrical holes, often of great depth, 

 under the heap, and there deposit their eggs surrounded by a 

 mass of dung in which they have previously enveloped them ; 

 thus not only dispersing the dung, but actually burying it at 

 the roots of the adjoining plants, and by these means con- 

 tributing considerably to the fertility of our pastures, sup- 

 plying the constant waste by an annual conveyance of fresh 

 dung laid at the very root ; by these canals, also, affording a 

 convenient passage for a portion of it when dissolved to be 

 carried thither by the rain. 



The coleopterous insects found in dung inhabit it in their 

 perfect as well as imperfect states : but this is not the case 



1 The Coprion, Cantharus, 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 an- 

 other to feed the Cantharus with some bread, who afterwards orders his companion 

 to give him another kind of bread made of asses' dung. 



