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NEW YORK STATE MUSEUM 



no other formations. The northern part of the township is wild 

 and unsettled, but the central and southern parts are well opened 

 by roads. Our observations have been chiefly limited to the 

 latter, but there is little doubt that the same rocks cover all the 

 area, unless gabbro dikes give local variety. Topographically 

 the township consists of a series of ridges with intervening val- 

 leys. 



Specimen 5 from the southwestern corner is a micaceous gneiss 

 of the general mineralogy of granite. Pegmatite lenses run par- 

 allel with the foliation. The strike is n 20 w magnetic. No. 6, 

 from a point 2 to 3 miles north and on the western border, is a 

 dark, massive gneissoid rock, probably one of the syenitic series 

 that is so largely developed in the townships just north in Ham- 

 ilton count}'. Belated types occur in Garoga township at S and 

 7. No. 9, from near the center of the township, is a most in- 

 teresting rock. To the eye alone it is a very finely laminated 

 quartzose gneiss, almost a quartzite. It has been greatly mashed 

 and granulated. Under the microscope it is chiefly quartz, but 

 contains in addition abundant needles of sillimanite and not a 

 few garnets. (See pi. 8, fig. a.) It is quite certainly a metamor- 

 phosed sandstone, which contained originally considerable alu- 

 minous material and some lime. Its strike is n 80 w magnetic. 



No. 10, from the east end of Tannery pond, is a micaceous 

 gneiss, consisting chiefly of copper colored biotite and greenish 

 feldspar. Its strike is e and w, magnetic, dip. 45 s. Xo. 12, from 

 Bleecker postoffice, is the same as 10, but strikes n and s mag- 

 netic. Xo. 11 is a dark, rusty hornblendic gneiss. 



Garoga 



Garoga lies west of Bleecker. Through its center passes the 

 meridian which marks the boundary between the area studied 

 by Prof. C. H. Smyth and that covered by us. Like Bleecker, 

 Garoga is wholly within the area of gneiss. Two large lakes are 

 contained within its boundaries, viz Canada lake and Garoga 

 lake. 



