412 LOWEST RED SANDSTONE. 



the preceding are the most usual, and it is unne- 

 cessary to prolong a catalogue of minute varia- 

 tions. 



THIRD DIVISION. 



Containing fragments of previous rpcks : of 



a conglomerated structure. Red sandstone con- 

 glomerate, or breccia, of mineralogists. 



A. The basis consisting of either of the preced- 

 ing fine varieties except F and G, Division Second, and 

 containing fragments of quartz only. 



B. Similar bases, with fragments of granite, or 

 gneiss, or micaceous schist, or quartz rock, or jasper, 

 or all of these, with quartz. 



C. The same bases, including F, Division Second, 

 with fragments of argillaceous schist. 



D. The base G, Division Second, containing 

 fragments of trap rocks. 



E. The bases A, B, C, D, E, Division Second, 

 containing fragments of sandstone, with or without 

 other fragments of previous rocks. 



It is easy to imagine a much greater variety 

 of compounds, and perhaps many others exist. 

 It is unnecessary to refine on these divisions, and 

 the preceding contain all those which, as far as I 

 have observed, possess distinct characters and 

 occupy important geological positions. 



