118 GEOLOGY. 



evidence of the contemporaneity of Man and the Mastodon [in iN". 

 America] as very douhtfalJ' G. A. L. 



Dana, Prof. James D. On Southern New England during the melting 

 of the Great Glacier. Amer. Journ. ser. 3, vol. x. pp. 168-183, 

 280-282, 353-357, 409-438 ; 8 figures in text. 



The Champlain deposits of S. New England prove that daring the 

 closing part of the melting of the Great Glacier there was a vast flood, 

 that during the Glacial Period and the beginning of the Champlain 

 Period there was no marine life in Long Island Sound, and that the 

 region subsided together with the more northern regions. The paper is 

 divided into the following parts : — I. The flood from the melting 

 Glacier: 1. Newhaven region, with map and 5 illustrative sections ; 

 2. Outside of the Newhaven region. II. Absence of marine life, &c. 

 (as above). III. Reindeers in Southern New England. IV. Depres- 

 sion of the land, or amount of subsequent elevation. V. Conclusions 

 (pp. 433-438) : 1. The amount of depression in S. New England during 

 the melting of the Glacier was probably 10 to 20 feet ; 2. The river- 

 valley formations are not marine ; 3. The height of the flood was the 

 chief cause of the height of the terraces ; 4. The heights of the streams 

 during the flood are given (from 80 to 237 feet above mean high tide 

 level) ; 5. The pitch of the stream during the flood is given ; 6. The 

 Champlain was a Eluvial Period. G. A. L. 



Dawson, G-. M. British North- American Boundary Commission. 

 Report on the Geology and Resources of the Region in the Vicinity 

 of the Forty-ninth Parallel, from the Lake of the Woods to the 

 Rocky Mountains ; with Lists of Plants and Animals collected, and 

 Notes on the Eossils. Pp. 379. Montreal, London, and New 

 York. 

 In ascending order the great rock-divisions occurring in the districts 

 visited are : — Laurentian, Huronian, L. and U. Silurian, Devonian, Car- 

 boniferous (doubtfully present), Permian and Trias wanting. Cretaceous, 

 Tertiary Lignite series, and, lastly. Glacial.. Principal Dawson gives an 

 Appendix on the Possil Plants. G. A. L. 



. On the Superficial Geology of the Central Region of North 



America. Quart. Journ. Geol. Soc. vol. xxxi. pp. 603-623 ; piap 

 and 2 woodcuts. 

 , The district described is bounded on the E. by the great rocky plateau 

 known as the " Laurentian Axis," on the W. by the Rocky Mountains. 

 These are the great watersheds of the country ; but there are two others, 

 transverse to these, which are not marked by any grand physical fea- 

 ture. The drift-covered regions are classed as follows : — 1. Plateau of 

 N. and E. Minnesota ; 2. Lowest Prairie-Level and Valley of the Red 

 River ; 3. Second Prairie -Plateau ; 4. Third Prairie-Plateau, stretch- 

 ing up to the base of the Rocky Mountains. The Laurentian Axis is 

 much glaciated ; and there is evidence of glaciers in the Rocky Moun- 

 tains. The former was glaciated by land-ice, which floated off during 



