390 GEOLOGY OF THE NABRAGANSETT BASIN. 



ridges begins, trending N. 20° E. for a distance of 200 feet. Just north of 

 a wood road the shales strike N. 30° E., with a dip of 85° to vertical. The 

 shales contain nodules of limestone which have yielded a few casts of 

 Agraulus strenuus. 



The ridges above described terminate at a point just south of the open 

 fields. About 300 feet northwestward, near the western edge of the open 

 fields, occurs locality 2. It is a knoll trending N. 15° W. and consisting 

 chiefly of reddish and greenish shales ; lying upon the top and western side 

 of the knoll are great limestone blocks whose position in the section can 

 not be accurately determined, but which have furnished all the fossils cited 

 as coming from locality 2. The bowlders seem to belong to layers in the 

 immediate vicinity, but to have been broken iip by the evidently strong 

 folding and shearing of the Cambrian strata in this region. 



The following fossils have been found at locality 2 : Obolella atlantica 

 Walcott, figured but not named in our report; Obolella crassa Hall, Scenella 

 reticulata Billings, Stenotheca curvirostra S. & F., Stenotheca rugosa var. 

 abrupta S. & F., Platyceras primcevum Billings, Hyolithes americanus, Hyoli- 

 thes communis var. emmonsi Ford, Hyolithes quaclricostatus S. & F., Microdis- 

 cus bellimarginatus S. & F., M. lobatus Hall, Olenellus walcotti S. & F. 

 (probably a young form of some known species), Ptychoparia attleboro- 

 ensis S. & F. (probably the young form of some species of trilobite), 

 Agraulus strenuus? Billings. 



Northwest of locality 2, on the other side of a fence, is another knoll, 

 trending N. 23° E., consisting chiefly of reddish and greenish shales, but 

 containing on the west side a few nodules of limestone which have afforded 

 Hyolithes and fragments of Agraulus. 



There is a similarity of trend between the Cambrian deposits at locality 

 1 and immediately northward, and at the margin of the granite hill imme- 

 diately to the westward of it. This is also true in a measure of the outcrops 

 south of the stream about 500 feet north of locality 1, and 500 feet south of 

 locality 2, where the quartzite shale and limestone beds strike northeastward, 

 while the granite hill on the west seems to make a similar deflection. 

 Again, at locality 3 and northwestward, the Cambrian strata strike north- 

 westward, apparently following the general trend of the eastern margin of 

 the granite hill. 



Quartzite occurs at the southeastern angle of Hoppin Hill, just north- 



