194 RECORD OF SCIENCE FOR 1886. 



15. Smith describes a bed of clay inclosed in the Delaware gravels 

 near Philadelphia. It contains remains of trees of species now living, 

 and appears to be similar in age to the other clay beds farther up the 

 Delaware valley.* 



16. D wight describes some very curious structural features in Oham- 

 plain deposits in the Hudson valley near Newburgh. At the locality de- 

 scribed there are three huge clay-filled pot-holes in a sand bed. These 

 holes are in line, close together and elliptical in outline, with their 

 longer axes at right angles to the Hudson. They appear to be in a 

 faulted block of the sand, and the fault line on one side is marked by a 

 hard wall composed of sand cemented by carbonate of linie.t 



17. Ashburner and Hill | describe the buried valley of the Susque- 

 hanna between Pittston and Kingston, in Luzerne County, Pa., and 

 discuss the former channel of that river and its peculiarities; Ash- 

 burner describes the Archbald potholes in the same vicinity, and from 

 their position considers them either due to water flowing beneath the 

 glacier or over its edge.§ 



18. Dawson describes the bowlder drift and sea margins at Little 

 Metis, Lower St. Lawrence. The bowlder drift occurs in belts exposed 

 at low tide, and extending out to some distance from the shore. The first 

 or shore terrace seldom holds bowlders, but farther inland there is a ter- 

 race 30 feet higher, consisting of sand resting on hard bowlder clay or 

 till, the latter sometimes being filled with bowlders and at others with 

 marine shells. Higher up huge bowlders are found perched upon the 

 bare rocks, the latter being rough and showing no sign of polishing 

 except near the second terrace. It is thought that these phenomena 

 can not be ascribed to land ice, and are similiar to those of the Lower 

 St. Lawrence generally, except in some lateral valleys on the northern 

 shore, where local glaciers appear to have descended. || 



10. Lamplugh describes the glacial shell beds of British Columbia, 

 adding detail to Dawson's previous descriptions. The beds at Esqui- 

 mault, Vancouver's Island, lie in a gully in polished and striated dio- 

 rite. The shells are abundant in the lower layers of the clays, and 

 decreasing in number upward, are absent ten feet from the surface. It 

 is thought that the beds were shoved up into this gully by the ice in 

 its flow down the channel, as they dip steeply shoreward and are often 

 disturbed. H 



20. Gilbert has discussed two instances of post-glacial deformation. 

 First, in a paper on the inculcation of scientific method by example, 

 he incidentally investigates the cause of the elevation of the center 

 of the Bonneville Basin. It is supposed that this great Quaternary 



*Philadelpliia Acad. Sci. Proc. vol. 37, pp. 253-254. 



t Vassar Bro's lust. Trans., vol. 3, pp. 86-97. 



t Second Geological Survey of Pa., annual report for 1885, pp. 637-647. 



^Ib., 615-637. 



II Canadian Record of Science, vol. 2, pp. 36-38. 



U Geol. Soc, Quarterly Jour., vol. 42, pp. 276-286. 



