PETROGRAPHIC GEOLOGY AND DESCRIPTIONS. 451 



Quartzyte.] 



a little diallagic. This distinction is not sharp. The section also shows some quartz 

 in large isolated grains. 



One section. 



Age. Cabotian(?) dike. N. H. w. 



No. 616. QUARTZYTE. (Metamorphosed.) 



Pigeon point. West side of the same little bay, north of the last. 

 Ref. Annual Report, ix, page G9; Annual Report, x, page 58. 



Meg. Spotted red and dark gray, medium grained. An incipient granite, 

 resembling some rock on the east side of the bay. 



Mir. (JiHirtz is abundant, but the matrix of the grains is stained red with oxide 

 of iron. The feldspars are unidentifiable as to species. N. H. w. 



No. 617. QUARTZYTE. 



Pigeon point. Prom near the base of the hill about half a mile west of the "Little portage," at the south 

 shore. 



Ref. Annual Report, x, page 58. 



Meg, A brown, hardened sandstone. 



Mir. Quartz grains, in a reddened cement, compose the most of this rock, but 

 amongst the latter may be seen some fibrous grains that are chloritic or hornblendic, 

 as well as some of mica. 



One section. 



Age. Animikie. N. H. w. 



No. 618. QUARTZYTE. (Metamorphosed.) 



Pigeon point. Near the summit of the same hill. 

 Ref. Annual Report, x, pages 58, 59. 



Gray quartzyte. 



Mir. This rock contains much granular quartz, constituting about two-thirds 

 of the whole, and some fine grains of plagioclase. Owing to the presence of several 

 lu//>ersthene crystals, which are, so far as discovered hitherto, characteristic of the 

 contact belt between the basic irruptives and the elastics of the region, as well as 

 the existence of remains of older plagioclases, this rock may have originated as one 

 of the "intermediate rocks" (of Bayley), i.e., it may have solidified from a new 

 magma produced by the fusion of some of the sedimentaries and the mingling of this 

 matter with the magma that rose from a deep source. The gray color of the rock is 

 not in keeping with that of the rock that results from the simple metamorphism of 

 the elastics, which produces a red rock. At least, hypersthene, as a mineral of the 

 basic rocks when cooling near the reactionary rim of the elastics, seems to point' to 

 this rock as a changed basic rather than as a changed quartzyte. One section. 



Age. Animikie at contact on a Cabotian intrusive. N. H. w. 



