O F F O S S I L S. 387 



but few variations, and /like wife ; as the num- 

 ber of the falts proper for thefe mixtures, is ex* 

 ccedingly limited; but / furpaftcs even m, 

 ({ *5fy > f that \vc huvc here another occafion 

 of admiring the exhauiliblc Aorics of nature. 



SCLXVI. The Pojiilon and Jit nation cf mixed 



I r is by no means to be expected ; that every 

 fpscies of thefc mixed tbilils, wliich to me appear 

 tobe/wtf/vr, flunild be equal to the production 

 of huge mountains. The grcatefl number of 

 them have hitherto been found in veins orfmall 

 flrataonly; many of which, though of different 

 characters, when combined, give birth to rocks. 

 The fame may be faid of the fcparatc particles, 

 which, in the aggregate, form large and- conti- 

 nued ridges of hills. But thefe a 1 mo fl always 

 fpring from the ruins and decompofuiorU of 

 mountains. 



S CL\VII. Species cf organic Fojfilf. 



ORGANIC foffils conditutc fourgcncra, (97.) ; 

 but the fcver.il fpccics of fulfils, whether poffciT- 

 ing an organic form only, or with it an organic 

 Aructure, arc diflinguifhcd by fpecific marks. 



5 CLXV1IJ. 



