530 I'.G. CLAPP GLACIAL PERIOD IN NEW ENGLAND 



In Maine they extend along the coast from Kittery to Eastport, forming 

 many low plains near the sea and extending np most of the river valleys. 

 In York county they extend 15 miles or more from the coast. In the 

 valley of Presumpscot river they are found nearly to Sebago lake ; in the 

 Androscoggin valley to beyond Lewiston and Mechanic Falls. In the 

 Kennebec valley they are found to contain marine fossils at Brunswick, 

 Bowdoinham, Gardiner, Augusta, Vassalboro, Waterville, and Skowhe- 

 gan. Farther north similar clays occur at higher elevations as far as 

 Solon, and they are foixnd in the valley of Sandy river at Farmington ; 

 but the clays above Skowhegan may possibly not be marine, as fossils 

 have not been reported in them. The marine clays are abundant along 

 Sheepscot river, in Lincoln coimty, and are widely distributed in the 

 vicinity of Eockland, in Knox county. They extend up Penobscot river 

 to beyond Oldtown. They are foimd in small patches on many of 

 the islands in Casco, Penobscot, and Bluehill bays, and are well exposed 

 on Mount Desert island and on the shores of Bluehill bay. In Washing- 

 ton county they form plains of moderate extent at many places near the 

 coast, and in places extend for miles inland along the valleys. They are 

 widely distributed in New Brunswick. 



Fossils. — The "Leda clays" have been studied by many writers, among 

 whom are J. W. Dawson, Jackson, C. H. Hitchcock, and Packard.* The 

 latter writer gave complete lists of. fossils from the various New England 

 localities and postulated certain theories regarding the climatic and 

 geologic conditions at the time the clays were formed. Many other 

 writers have given names of species found in various localities, but have 

 not made any extensive investigations on the subject. 



As differences in Pleistocene faunas are due chiefly to slight differences 

 in climate, it is not supposed that correlations between the several clay 



* J. V,'. Dawson : On the newer Pliocene and post-Pliocene of the vicinity of Montreal. 

 Canadian Naturalist. 1857. 



Additional notes on the post-Pliocene deposits of the Saint Lawrence valley. Canadian 

 Naturalist, 1859. 



On the climate of Canada in the post-Pliocene period. Canadian Naturalist, 1860. 



On post-Tertiary fossils from Labrador. Canadian Naturalist. I860. 



On the geoloay of JIurray bay (part 3, post-Pliocene deposits). Canadian Naturalist, 

 1861. 



On the post-Pliocene deposits of Riviere du Loup and Tadoussac. Canadian Natural- 

 ist, 1865. 



The post-Pliocene geology of Canada. Canadian Naturalist, second series, vol. vi, 

 1872, pp. 19-42, 166-187, 241-259. 



C. T. .Jackson : First, second, and third reports on the geology of the state of Maine, 

 1837-1839. 



C. H. Hitchcock : Notes on the geology of Maine. I'roc. Portland Soc. Nat. Hist., vol. 

 1, part 1, 1862, pp. 72-85, and numerous other references. 



A. S. Packard, Jr. : Observations on the glacial phenomena of Labrador and Maine. 

 Mem. Boston Soc. Nat. Hist., vol. 1, 1865, pp. 210-303. 



