232 NATURAL HISTORi 



tinites, chamites, teeth and bones of fish, also fish much 

 mutilated, tortoises, crabs, alcyonites, madreporites, spon- 

 gites, and encrinites.* 



VII. Flcetz Trap Rocks. 



These rocks occur in several of the floetz formations 

 already mentioned, either as subordinate beds, or in 

 mountain masses. In the red sandstone formations they 

 occur in beds, veins, and mountain masses, and appear 

 in single hills, as Salisbury Craig, near Edinburgh, or in 

 ranges of hills, as the Pentlands and Ochils, also near 

 Edinburgh. The only rock of the series which contains 

 petrifactions is the trap-tuff, which includes a few vege- 

 table impressions. 



Flo3tz trap rocks also occur in the floetz limestone for- 

 mation, either in beds or mountain masses; and some- 

 times we meet with whole ranges of such hills belonging 

 to the floetz limestone. I do not know that petrifactions 

 have ever been found in the trap of these formations. 



The Coal Formation, which forms a great tract of 

 country on both sides of the Frith of Forth, contains 

 beds and veins of floetz trap rocks. The only trap rock 

 of this series which contains petrifactions is the trap- 

 tuff, and it very rarely presents a few vegetable impres- 

 sions. 



VIII. Newest Flcetz Trap. 



The newest floetz trap formation of Werner, which is 

 of a very late date, contains very few petrifactions. 



* I enumerate in this list the petrifactions discovered by Faujas St. 

 Fond in the Petersberg, near Msestrich, as it is the opinion of some 

 naturalists that it belongs to the chalk formation. 



