1890.] NATURAL SCIENCES OF rillLADELPIIIA. 97 



•quarter of a mile northwest is garnetiferous mica schist in place, and 

 one hundred yards further northwest Potsdam sandstone. 



At the outcro]) northwest of Radnor station garnetiferous schist 

 and gneiss were disclosed in a well not over two hundred feet north 

 of the serpentine. In the strike line (southwest) and to the south- 

 cast Laurentian fragments abound. About five hundred feet north- 

 east of the northeast end of this exposure runs the Radnor and King 

 of Prussia road. On this, to the northwest of the line of strike is an 

 outcrop of Laurentian in place, while to the southeast and very close 

 to the strike line is a very hard porphyritic contorted mica schist 

 unlike any other outcrop of the region. 



Further west, between Radnor and AVest Chester, the serpentine 

 is much concealed, but there are some outcrops of interest. 



The most important of these lie a little less than a mile south of 

 the Pennsylvania Railroad, near Paoli, Green Tree and Malvern sta- 

 tions and among the headwaters of Crum creek. Southeast the 

 Laurentian is apparent, here and there in conspicuous outcrops. On 

 the road leading to Malvern, we find, going north northwest, as 

 follows : 



feet. 

 Laurentian, 

 Low ground, . . . . . . . . .100 



Serpentine, ......... 250 



Low, .......... 50 



Garnet staurolite schist, ....... 100 



Low, 500 



Garnet staurolite schist, 100 



Trap, 50 



Garnet staurolite schist, ....... 200 



Serpentine, . . . . 400 



Low, 300 



Garnet staurolite schist, ....... 200 



Concealed, 300 



Hydromica schist of the South (Chester) Valley Hill, . 5000 



Showing here two distinct outcrops of the serpentine, with mica 

 schist between them, and beyond the northernmost. 



About half a mile east of the ]Malvern road is a nearly parallel road 

 leading to Green Tree. On a road connecting the two, just south 

 of the serpentine, Laurentian is conspicuous. Going N. X. W. on the 

 Green Tree road, the belt is again divided, the southerly outcrop being 



