430 LIFE OF THE PLEISTOCENE 



1873. Report on the Geology of Cuyahoga County. Geol. Surv. Ohio, I, Geology 

 and Paleontology, Chapter VI, pp. 171-200. 



1874. Surface Geology. Geol. Ohio, II, Chapter XXX, pp. 1-80. 



1874a. (Remarks on skulls of Dicotyles compressus found at Columbus, Ohio.) Proc. 



Lye. Nat. Hist. N. Y., (ii), No. 3, pp. 77-78. 

 1874b. (Remarks on Castoroides ohioensis.) Proc. Lye. Nat. Hist. N. Y., (ii), No. 4, 



pp. 92-93. 

 1883. On the Origin and Drainage Features of the Basins of the Great Lakes. Proc. 



Amer. Phil. Soc, XX, pp. 91-95. 

 1895. The Flora of the Amboy Clays. Mon. U.'S. Geol. Surv., XXVI (p. 109), pp. 



1-260. 

 Norton, William H. 



1895. Geology of Linn County. Geol Surv. Iowa, IV, Pleistocene Deposits, pp. 168- 



184. 

 1901. Geology of Cedar County. Op. cil., XI, pp. 343-372. 

 Nylander, Olof O. 



1901. Shells of the Marl Deposits of Aroostook County, Maine, as compared with the 



Living Forms in the same Locality. Nautilus, XIV, pp. 101-104. 

 1909. Fossil and Living Shells found in Little Mud Lake, Westmanland, Aroostook 



County, Maine. Nautilus, XXII, pp. 105-106. 

 Orr, Ellison. 



1908. Exposures of Iowan and Kansan(?) Drift, East of the usually accepted West 

 Boundary Line of the Driftless Area. Proc. Iowa Acad. Sci., XIV, 1907, pp. 

 231-236. 



Ortmann, Arnold E. 



1912. Notes upon the Families and Genera of Najades. An. Carnegie Mus., VIII, 

 No. 2, pp. 222-364 



1912a. The Geological Origin of the Freshwater Fauna of Pennsylvania. Top. and 

 Geol. Surv. Penn., 1910-1912, Appendix E, pp. 135-149. 



1913. The Alleghenian Divide, and Its influence upon the Freshwater Fauna. Proc. 

 Amer. Phil. Soc, LII, pp. 287-390. 



Orton, David. 



1878. Report on the Geology of Warren County. Geol. Ohio, III, pp. 381-391. 

 Orton, Edward. 



1873. Geology of the Cincinnati Group. Report on the Third Geological District. 

 Hamilton, Clermont, Warren and Butler Counties. Geol. Ohio, I, pp. 364-480, 

 (427-428.) 



1874. Report on the Third District. Geol. Ohio, II, pp. 609-696. 



1888. The Geology of Ohio, considered in Its Relation to Petroleum and Natural Gas. 



Geol. Surv. Ohio, VI, pp. 1-831. 

 1891. On the occurrence of Megalonyx jeffersoni in Central Ohio. Bull. Geol. Soc. 



Amer., II, p. 635. 

 Osborx, H. F. 



1899. The Newburgh Mastodon. Science, N. S., X, p. 539. 



1907. A Mounted Skeleton of the Columbian Mammoth (Elephas columbi). Bull. 



Amer. Mus. Nat. Hist., XXIII, pp. 255-257. 



1909. Cenozoic Mammal Horizons of Western North America. Bull. U. S. Geol- 

 Surv., No. 361, pp. 1-138. 



1910. The Age of Mammals. In Europe, Asia, and North America, pp. i-xvii, 1-635. 

 New York, Macmillan Company. 



