T. Sterry Hunt on Granite Rocks. 119 
who looked upon them as having been formed by igneous 
structure, their drusy cavities, the peculiar incrustations and 
modes of enclosure often observed in the crystals, and finally 
~ variety found in the Schischimskian Mountams in the Urals is the gangue 
diamonds, which are found abundantly in microscopic crystals im in i 
ine. The seybertite of this region (the xanthophyllite of G. Rose) is described 
in taleose slate with serpentine (which also include diamonds), 
tian rocks it is only known in calcareous veinstones with spinel, 
hite, etc. 
ul For a notice of the eccurrence of leucite in these veins, and aiso in veins in 
Peeing see the author’s Contributions to Lithology (this Journal, II, xxxvii, 264). 
ccording to Garrigou, this rare species occurs well ized and in com- 
pact porphyroid masses, in dioritic rocks (ophites) at Lusbé in the valley of Aspé, 
in the Pyrennees (Bull. Soc. Geol. de Fr., Il, xxv, 727). 
