2 . P11YSIOG11APHY. CLASS II. 



Augite, occurs in imbedded crystals. Conchoidal Augite re- 

 fers to imbedded grains, whose fracture is perfectly con- 

 choidal ; common Augite occurs also in grains, but. having 

 an uneven fracture. Foliated Augite is transformed by 

 decomposition, into those earthy masses which have been 

 called crystallised Green -earth. Coccolite is of rather paler 

 shades of green colours than the preceding varieties, and 

 consists of very distinct granular particles of composition, 

 which may be easily separated. The colours of SaJilite are ge- 

 nerally paler green, and inclining to grey ; it is faintly trans- 

 lucent on the edges, though there are some varieties of it as 

 black and opake as Augite. It is compound parallel to the 



face of . If the colours become very pale, it passes 



into Diopside, which contains greenish-grey, greenish-white, 

 &c., and semi-transparent crystals, or massive varieties 

 also of pale colours, and compound parallel to the face of 

 Pr 4- 03. The latter is also the case in those dark-green va- 

 rieties of common Actinottte which belong to the present 

 species. Baikalitc cannot be distinguished from Sahli te, even 

 by such slight marks as those just quoted, and Fassaite is 

 the name of those varieties which unite the green colours 

 of Sahlite, or some that incline still more to yellow with 

 crystalline forms, similar to those of Diopside. Omphazite 

 is a compact leek -green variety, with an imperfect conchoi- 

 dal or splintery fracture, and generally mixed with dode- 

 cahedral Garnet. That variety of granular Actinolitc which 

 belongs to the present species, and which has often been 

 called green Diallagc, is grass-green, either crystallised or 

 massive, and in the latter case it presents a granular struc- 

 ture, or is composed parallel to _ or to Pr + cs, alternat- 

 ing in layers with particles of the following species, of the 

 same colour. Very delicate crystals produce a kind of 

 Asbestus, which is different from the one in connexion with 

 hemi- prismatic Augite-spar, and different also from Picros- 

 mine, a species that will be noticed in the Appendix. 



2. The following analyses will shew the range of the 

 constituent parts in the present species. 



