THE 



PHILOSOPHICAL MAGAZINE 

 AND JOURNAL. 



31" JANUARY 1823. 



I. On Animals receiving their Nutriment from Mitieral Sub- 

 stance. By the Rev. W. Kirby, M.A. F.R.S. F.L.S. 



To the Editors of the Philosophical Magazine and Journal. 

 Gentlemen, Barham, Jan. 16, 1823. 



ly/f IRBEL has proposed to distinguish vegetables from ani- 

 -'-'-■- mals by the different nature of tJieir food : the former 

 deriving their nutriment, as he affirms, from inorganic matter, 

 and the latter from organic. Anotlier able and learned phy- 

 siologist. Dr. Virey, in the Nmiveau Dictiotmaire d'Histoire 

 Naturelle, article Aliment, maintains, on the contrary, that 

 plants as well as animals are supported by organic food; since, 

 as he contends, it is the debi'is of organized matter, mixed with 

 the soil, that furnishes plants with tneir appropriate pabulum, 

 as likewise those animals, such as earthworms, the larvae of 

 ephemerae, &c. which have been suj)posed to live upon earth. 

 He also excludes water and air from the function in question. 

 The arguments which he adduces in support of his hypothesis 

 appear ingenious and forcible: the principal one is, that the 

 fertility of a soil depends upon the quantity of humus or vege- 

 table earth that it contains ; and that worms, &c. are not to be 

 found in very barren soils. Still, however, there is no general 

 rule without some exceptions : and one has fallen under my own 

 notice, whicli seems to prove that there are animals that can 

 derive nutriment from a mineral substance, in which there are 

 no debris of organized matter. When I was lately in town, 

 Mr. Hunneman, of Queen-street, Soho, informed me that he 

 had received some specimens of asbestos from Professor Bo- 

 nclli, which uj)on examination were found to contain many 

 larva,' of some insect, that had jjcrforated it in various direc- 

 tions, and in it underwent their customary metamorphoses. 

 These, when arrived at their perfect state, proved to be a species 

 of beetle of the genus Dcnnestes — u tribe Uial usually feeds 

 upon dead aniina< mailer wlien dried. He obligingly gave 



Vol. GI. No. 2r»7. ./««, jr>2.'}. A 2 * me 



