392 GEOLOGY OF THE NABRAGANSETT BASIN. 



geological position of these shales is unknown. Next the depot and north- 

 ward occur exposures of arkose, undoubtedly Carboniferous. It is possible, 

 however, that the red shales in question still belong to the Olenellus Cam- 

 brian, which is here again overlain by the Carboniferous. 



VALLEY OF LOCALITY 3. 



The road across Hoppin Hill leads from locality 1, first westward, then 

 southwest, nearly south, then again west until a small stream is crossed. 

 A short distance west of the stream is a house. Along the farm lane to the 

 northward red limestone bowlders appear in the fence wall on the left side of 

 the way. The bowlders increase in frequency as the end of the lane 

 is approached. At the northeastern end of the field, just west of the 

 northern end of the lane, red shale is exposed in the soil. The limestone 

 bowlders probably belong in situ somewhere among the red shales of the 

 vicinity, but at the present time their precise location can not be determined. 



The above-mentioned limestone bowlders have furnished the following 

 fossils: Obolella crassa, Scenella reticulata, Stenotheca rugosa var. abrupta, 

 Hyolithes communis, possibly also S. communis var. emmonsif Microdiscus 

 bellomarginatus, and Agraulus strenuus. Judging from the fauna alone, local- 

 ity 3 belongs to the horizon of locality 2, rather than to that of locality 1. 

 No quartzitic layers have been observed in this valley, and the actual expo- 

 sures, as already stated, are confined to red shales. The Olenellus Cambrian 

 deposits of this valley are bordered on the east by the granite of Hoppin 

 Hill. Toward the northwest occur several granite exposures, evidently 

 connected beneath the soil, and trending approximately north and south. 

 Directly west there are no exposures, but if there be any Cambrian in this 

 direction it is probably overlain by the Wamsutta Carboniferous, which is 

 known to occur considerably farther westward in the valley of Abbotts 

 Run. In this direction arkose, possibly near the base of the Carboniferous, 

 occurs about a mile north of locality 3, on the road from North Attleboro 

 to Arnolds Mills, and is quite abundant eastward as far as North Attleboro. 

 Wamsutta Carboniferous conglomerate occurs also a mile and a half south 

 of locality 3, apparently covering the Olenellus Cambrian in this direction. 

 Red shales occur at various points west and southwest of South Attleboro, 

 but so close to Wamsutta Carboniferous exposures that it is impossible for 

 the present to consider them as of Olenellus Cambrian age. It may, how- 



