240 



Some soils may be uue to the decay of animal 

 matter. Off the coast of South America there are 

 large deposits of guano, which are generally believed 

 to be due to vast accumulations of the excrements 

 of birds. It has, however, been shown by the late 

 Dr J. R. Kinahan that the guano accumulated on 

 the Chinchas Islands, Peru, are not the excrements of 

 birds, but " are formed of layers of seals' dung and 

 decayed seals, the denser, white, thin layers being 

 made up of the former, and the more friable, darker, 

 thick layers of the latter," as the sea-lions resort in 

 hundreds to such places to die. At the same time this 

 observer does not wish to state all guano is similarly 

 formed, as the guano from Ichaboe and South Aus- 

 tralia is so different from that of Peru that they 

 would seem to have a different origin.* 



* Journal of the Royal Dublin Society, July i856, pp. 89 et seq. 



PRINTED BY BALLANTYNE AND COMl'ANY 

 EDINBURGH AND LONDON 



