I 



AMEEICA. 131 



granite, metamorphic rocks, and sandstones, overlain by Tertiary beds, 

 the upper part of which are Miocene. G. A. L. 



Dana, Prof. J. D. Note on the " Chloritic formation " on the -western 

 border of the New Haven Eegion. Amer. Joimi. ser. 3, vol. xi. 

 pp. 119-122. 



Gives the petrographical characters of the massive and slaty rocks in 

 this formation. They are metamorphic ; and the former contain labra- 

 dorite as a prominent constituent, and are in appearance very like trap. 

 The formation contains two or more beds of limestone, and is probably 

 L. Silurian. The labradorite is perhaps due to two conditions in tho 

 original mud-beds — the presence of a comparatively small percentage 

 of silica, and of disseminated carbonate of lime from fossils. G. A. L. 



Green Mountains. Amer. Journ. ser. 3, vol. xi. p. 151. 



Corrects some topographical descriptions. The metamorphic rocks 

 of which these mountains consist are not younger than Silurian ; but 

 the trap-ridges of the Connecticut Valley are Jurassic. G. A. L. 



. On the Damming of Streams by drift ice during the melting 



of the great Glacier. Amer. Journ. ser. 3, vol. xi. pp. 178-180. 



Gives reasons for thinking that the height of the upper terraces, 

 above the narrows of the rivers of tho district referred to, was partly 

 owing to the cause mentioned in the title. (See Geological Eecord for 

 1875, p. 118.) G. A. L. 



. Glacial Mood. Amer. Journ. ser. 3, vol. xii. pp. 64, Qb. 



Eefers to a paper by Prof. Winchell " On the Drift-deposits of the 

 North-west," in the Pop. Set. Monthly, July 1873. 



. [Glacial action in America.] iV. Jahrh. Heft i. p. 43. 



The tibia of a reindeer has recently been got from a Glacial clay, 

 4 miles N. of New Haven. 



Darwin, Charles. Geological Observations on the "Volcanic Islands 

 and parts of South America visited during tho Voyage of H.M.S. 

 ' Beagle.' Ed. 2, pp. xiii, 647, maps, sections, and plates of fossils. 

 8vo. London. 

 Except for verbal corrections and alterations, and the addition of 

 some supplementary observations on the thickness of the Pampean for- 

 mation near Buenos Ayres (pp. 363-369) (from Quart. Journ. Geol. Soc, 

 ] 862), this is identical with the first edition. Pp. 1-185 refer to tho 

 Volcanic Islands, and pp. 187-627 to S. America. J. W. J. 



Dawkins, Prof. W. B. On Silver Mining in Nevada. Proc. Lit, 



Phil. Soc. Manch. vol. xv. pp. 141, 142. 

 Silver lodes 12 feet wide occur 12 miles from Batch Mountain, a 

 station on the Central Pacific Railway. 



Dawson, Dr. J. W. Notes on the Occurrence of Eozoon canadense 



x2 



