Granites of Cecil County, in North-eastern Maryland. 67 



crystals. Both the schist and the staurolite crystals are 

 dotted over with red garnets In the small depressions along 

 the hillsides, good crystals, which reach an extreme length of 

 two inches, can be collected in large numbers. Single crystals 

 are the most abundant, though twins of the two kinds usual 

 for staurolite occur. 



Passing from this typical locality of Basin Run to the 

 south-west, the staurolite decreases in amount, so that in 

 three-quarters of a mile it disappears, but the crumpled schist 

 is still filled with garnets. If followed in the opposite direc- 

 tion the schist itself disappears, but in an area outside of the 

 map and three miles to the east, near a village known as 

 Principio, a small outcrop of a similar staurolite schist was 

 seen. 



Throughout the area, between the staurolite mica schist 

 described and the gabbro mass at the north, the granite is 

 massive and exhibits but little of the gneissoid appearance, 

 while exposures of dioritic dykes and blocks resulting from 

 their decomposition are very few. In these points this area 

 offers a marked contrast to that south of the schist, where 

 the granite is distinctly foliated, and where dioritic belts 

 occur in large number. On account of these differences, it 

 is thought best, for purposes of description, to use this schist 

 as a division line in the area. The region north of the 

 staurolite zone will be considered in the next chapter as the 

 Rowlandville Area, and that south will be described in the 

 third chapter as the Port Deposit Area. 



(TO BE CONTINUED.] 



