604 VOLCANIC ROCKS. 



SECOND SUBDIVISION. 



Loose. 



A. Fragments of various rocks, both primary and 

 secondary, more or less altered by the fire. 



B. Powdery matters : puzzolana, ashes, dust. 



The following catalogue contains the principal 

 imbedded minerals which have been observed in 

 volcanic rocks. It is unnecessary to add the 

 names of the amygdaloidal minerals already men- 

 tioned. 



Felspar. Melanite. 



Pyroxene. Idocrase. 



Hornblende. Tourmalin. 



Garnet. Apatite. 



Peridot. Jargon. 



Mica. Pseudo-sommite. 



Hauyne. Ice spar. 



Meionite. Pleonaste. 



Melilite. Arragonite. 



Tabular spar. Oxidulous iron. 



Sommite. Sphene. 



Leucite. Copper. 



Other minerals have recently been introduced 

 into the catalogue as found in similar situations; 

 but as these new species are not yet thoroughly 

 1 established, I forbear to quote them. 



