1886,] Mineralogy and Petrography. 549 
of a highly metamorphic aspect,” which “has been made out of 
a diorite or a hornblende schist.” In some of the gneisses 
Spinel, twins of zonal olivine, twinned anorthite, chromiferous 
pyroxene in twinning relation with large bands of eustatite and a 
little black Secondary mica. Bronzite often occurs in large 
crystals, giving the rock the appearance of a porphyrite. Oph- 
itic rocks from the Same region are composed of titanic iron, 
labradorite and pyroxene, with a little olivine in the most basic 
Varieties, 
"CE. AMERICAN NATURALIST. December, 1885, p. 1215, and G. H. Williams, 
Amer. Jour, Sci., October, 1884, p. 259. 
The Geological Magazine, March, 1 886, p. 103. 
i "Ib. October, 1884, P- 440. 
*Comptes Rendus, Mars 1 5, 1886, p. 640. 
*Ib., Mars 22, 1886, p. 709. 
