550 CENOZOIC TIME. 



north, that is, in the direction of the flow. Further, the effect of waves is apparent in 

 the fiow-and-plunge structure of the obliquely-laminated beds. (Fig. 942.) Such beds 

 are usually as much as six inches thick, but occasionally six to eight feet. A thick- 

 ness even of six inches is proof that vast amounts of sand and gravel were at the dis- 

 posal of the currents and waves, and that the deposition went forward with great ra- 

 pidity. 



The height of the sea-border formations increases in going north, like 

 that of the river-border and lake-border formations. On the southern 

 shores of New England, the height above the sea is 40 to 50 feet ; on 

 Nantucket, 85 feet ; at Point Shirley, near Boston, 75 to 100 feet ; on 

 the coast of Maine, in some places, 217 feet; on the shores of Lake 

 Champlain, at different heights, up to 393 feet above tide-level, and 

 containing marine shells to a height of 325 feet ; on the borders of the 

 St. Lawrence, with abundant marine fossils, near Montreal, to a height 

 of 470 feet. From this point, the same formations continue on, and 

 border Lake Ontario ; but they are destitute of marine remains, — the 

 flow of fresh waters in the river St. Lawrence beyond having appar- 

 ently prevented the farther ingress of the ocean and of marine life. 

 On the coast of Labrador, the beds are 400 to 500 feet above the sea. 

 They occur also in the Arctic regions in many places, as on Cornwallis 

 and Beechy Islands in Barrow Straits, where they are at different 

 heights to 1,000 feet. 



The seashore deposits on Nantucket occur at Sancati Head. In Maine, the beds occur 

 at many places near the coast, as Portland, Cumberland, Brunswick, Thomaston, Cher- 

 ryfield, Lubec, Perry, etc., at different elevations, not exceeding 217 feet, so far as j'et 

 reported; also distant from the coast, at Gardiner, Hallowell, Lewiston, Skowhegan, 

 Clinton Falls, and Bangor. At Lewiston, a starfish and various shells were found in a 

 bed 200 feet above the ocean and 100 above the Androscoggin River; at Skowhegan, 

 the beds are 150 feet above the ocean, and 100 feet at Bangor; near Mt. Desert (a sea- 

 bottom deposit, on North Haven Island), 217 feet. 



There are shell-beds at several levels and man}' localities, along the St. Lawrence, 

 observed by Logan; and part, as Dawson has shown, are sea-beaches, and others off- 

 shore deposits. At Montreal, at heights of 470, 420, 366, 200, 100, above the river, or 

 20 feet more for each above Lake St. Peter; west of Montreal, near Kemptville, at a 

 height of 250 feet; on the Upper Ottawa, 65 miles northwest of Ogdensburg, 360 feet; 

 in Winchester, 300; in Kenyon, 270; in Lochiel, 264 and 290; at Hobbes Falls in Fitz- 

 roy, 350; at Dulham Mills, 289; in the counties of Renfrew, Lanark, Carlton, and 

 Leeds, 425 ; east of Montreal, near Upton Station, 257 ; farther east, on the river Gouf- 

 fre, near Murray Bay, 130 and 360 feet. At the Straits of Belle Isle, Labrador, the 

 terraces, on either side, are about 400 feet above the sea; at Chateau Bay, 500 feet, prob- 

 ably 800 feet in some parts (Packard). 



The 100-foot level near Montreal was apparently beneath the sea at the time, as the 



shells in which it abounds are not littoral species, neither are the specimens water-worn. 



At Beauport, near Quebec, there are thick beds of this kind, mostly made of shells, 



partly littoral, and situated at heights of 200 to 400 feet above the sea. The depth of 



water inferred for these deep-sea beds by Dawson, from the species of shells, is 100 to 



300 feet. Dawson makes the marine formation in Canada to consist (1) of unstratified 



bowlder-clay; (2) deep-water clays just mentioned, called Leda clays, from one of the 



fossils; (3) the overlying shallow-water sands and gravels, called also the Saxicava 



sands. 



The more common shells of the Montreal beds are the following (Dawson): Saxicava 



