AMERICA. 123. 



Upper and Lower Silurian (Clinton Shale to Potsdam Sandstone). 

 A great fault at the foot of Bald-Eagle Mountain is described ; and the 

 great erosion of the country is noticed and illustrated by sections 

 showing the former extent of the beds. The ores are considered to bo 

 deposits of iron, as hydrated peroxide, set free from the limestones 

 during their slow erosion and dissolution ; and the processes of their 

 formation are sketched out. The hematite occurs in pockets, as sur- 

 face-washes, and in beds. The total visible thickness of Lower Silurian 

 Limestones is 7750 feet. Practical Value of the Ores. Probable 

 Quantitij of Ore. Special Descriptions (pp. 32-83). Gives details of 

 the Pennington Range, Warrior's Mark, and Lovetown Range, Dry- 

 Hollow Range, Cale-HoUow Range, and Spruce-Creek Range. A 

 chemical investigation of the ores by Dr. Genth (see joost) seems to be 

 interpolated after p. 83, Prof. Lesley's paper continuing at p. 99 with 

 a description of Mining Methods. The Fossil Ore Belt is, lastly, de- 

 scribed (pp. 102-107). W. W. 



Lesqiterefx, Prof. Leo. On the Formation of the Lignite Beds of 

 the Rocky-Mountain region. Amer. Journ. ser. 3, vol. vii. pp. 

 29-31. 



Rejects the view that these beds have been formed by the heaping-up 

 of drifted materials. 



. On Remains of Land Plants in the Lower Silurian, Amer, 



Journ. ser. 3, vol. vii. pp. 31-34. 

 Confirms the discovery of land-plants in the clays of the Lebanon 

 Beds, in Longstreet Creek, at the base of the Cincinnati group. The 

 specimens belong either to Sigilkiria Serlii or >S^. Menardi. G. A. L. 



. On the Age of the Lignitic formations of the Rocky Mountains, 



Amer. Journ. ser. 3, vol. vii. pp. 546-557. 



An answer to Dr. Newberry's criticisms [see p. 125]. The author's 



views regarding these Western Lignites are thus given : — 1. The Lower 



Lignitic : that of Black Butte, the whole Colorado Basin as far south 



into New Mexico as the Placiere anthracite coal has its flora Eocene : 



Lower Eocene for America. 2. The Evanston coal is half Eocene, half 



Pliocene, referred as yet to the Upper Eocene. 3. The flora of Carbon 



is Middle Miocene. 4. That of Green River, Elko Station, and the 



Parks is of Upper Miocene type. G. A. L. 



LoEW, 0. Lieutenant Wheeler's Expedition nach Neu-Mexiko und 



Arizona. [Wlieeler's expedition to New Mexico and Arizona.] 



Pctermann's Mittheilungen, Bd. xx. pp. 401-410, 453-401, map 



[not geological]. 



Account of the results of the expedition, chiefly geographical, but 



with occasional geological notes. 



Martin, D. S. Cretaceous in Long Island. Proc. Lye. Nat. Hist. N. 



York, ser. 2, no. 4, p. 127. 

 Remarks confirming Prof. Hitchcock's belief in the presence of beds 

 of this ago in Long Island. 



