Authors' Catalogue. 243 
Leonard, A. G. 
Geology of Dallas county [Iowa]. (Iowa Geol Survey, vol. 8, pp. 
51-118, pis. 4-6, 2 maps, 1898.) 
Leverett, Frank. 
The weathered zone (Sangamon) between the lowan loess and 111- 
inoian till sheet. (Interglacial deposits in Iowa: A symposium pre- 
sented at the Iowa Academy of Sciences, Des Moines, Iowa, Dec. 
28, 1898; pp. 8-17, I map, I pi. Reprinted from Proc. Iowa Acad. 
Sci., vol. 5, 1898.) 
Leverett, Frank. 
The weathered zone (Yarmouth) between the Ulinoian and Kan- 
san till sheets. (Interglacial deposits in Iowa: A symposium present- 
ed at the Iowa Acadeiny of Sciences, Des Moines, Iowa, Dec. 28, 1897; 
pp. 18-23. Reprinted from Proc. Iowa Acad. Sci., vol. 5.. 1898.) 
Luther, D. D. 
The stratigraphic position of the Portage sandstones in the Naples 
valley and the adjoining region. (15th Ann. Rept. State Geol. of New 
York, pp. 2.2,2,-2z(i, i pi., i map, 1897.) 
Luther, D. D. 
The economic geology of Onondaga county. New York. (15th 
Ann. Rept. State Geol. of New York, pp. 22,']-Z02„ 20 pis., 2 maps, 
1897.) 
Martin, G. C. 
An occurrence of dunite in western Massachusetts. (Am. Jour. 
Sci., ser. 4, vol. 6, pp. 244-248, Sept. 1898.) 
Miller, W. G. 
Economic geology of eastern Ontario. Corundum and other min- 
erals. (Rept. Bureau of Mines of Ontario, vol. 7, pt. 3, pp. 207-238. 
6 pis., I map, 1898.) 
Moses, A. J. 
An introduction to the study and experimental determination of the 
characters of crystals Chap. XI. (School of Mines Quarterly, vol. 
19, pp- 374-391. July, 1898.) 
Packard, A. S. 
A half-century of evolution, with special reference to the effects 
of geological changes on animal life. (Science, new ser., vol. 8, pp. 
243-257, Aug. 26, 1898; pp. 285-294, Sept. 2, 1898; pp. 316-323, Sept. 9, 
1898.) 
Reid, H. F. 
The variations of glaciers. III. (Jour. Geol., vol. 6. pp. 473-476, 
July-Aug., 1898.) 
Ries, Heinrich. 
Physical tests of the Devonian shales of New York state to deter- 
mine their value for the manufacture of clay products. (15th Ann. 
Rept. State Geol. of New York, pp. 673-698, 1897.) 
