weeks] PALEONTOLOGY, PETROLOGY, AND MINERALOGY, 1894. 63 
333a Keyes (Charles Kollin). Goal deposits of Iowa. 
Iowa Geol. Surv., vol. ii, p. 536, pis. i-xviii, figs. 1-222. 
Discusses the origin of coal. Describes the geologic features of the 
Carboniferous basin of the Mississippi Valley, the geology of the coal 
area, the lithologic and stratigraphic characteristics of the Coal Meas- 
ures, and the local features of the coal beds of the various counties of 
the State. 
334 Cretaceous formations of northwestern Iowa. 
Abstract : Iowa Acad. Sci., Proc, vol. i, pt. iv, pp. 21-25. 
Mentions the subdivisions of the Cretaceous found in this part of 
Iowa. 
335 Derivation of the Unione fauna of the Northwest. 
Iowa Acad. Sci., Proc, vol. i, pt. iv, pp. 25-29. 
Describes the geographic and geologic distribution of Unionfdae in 
North America. 
336 Process of formation of certain quartzites. 
Abstract : Iowa Acad. Sci., Proc, vol. i, pt. iv, pp. 29-31. 
Describes the formation of the Sioux quartzite of Iowa. 
336a The Coal Measures of Iowa. 
Abstracts : Eng. and Mg. Jour., vol. lvii, pp. 269-270, 295-297, and 317- 
318; Am. Geol., vol. xiii, pp. 353-354. 
Noticed in Bibliography and Index for 1892 and 1893. 
33(\b Some Maryland granites and their origin. 
Review: Am. Geol., vol. xiii, p. 63 (+p.). 
Noticed in Bibliography and Index for 1892 and 1893. 
330c Epidote as a primary constituent of eruptive rocks. 
Review: Am. Geol., vol. xiii, p. 63 (i p.). 
Noticed in Biliography and Index for 1892 and 1893. 
336d Kindle (E. M.), Marsters (V. F.) and. Geologic literature of 
Indiana (stratigraphic and economic). 
Ind. Acad. Sci., Proc, 1893, pp. 156-191. 
See Marsters (V. F.) and Kindle (E. M.), No. 402. 
33(ie King (Clarence). The age of the earth. 
Smith. Inst., Ann. Kept., 1892-93, pp. 335-352. 
Noticed in Bibliography and Index for 1892 and 1893. 
337 King (Francis P.). A preliminary report on the corundum depos- 
its of Georgia. 
Ga. Geol. Surv., Bull. No. 2, pp. 133, with geologic map of north 
Georgia. 
Gives a historical sketch of corundum and a description of its phys- 
ical features, alterations, and associate minerals. Describes its geo- 
graphic and geologic distribution in Georgia, and gives a list of 33 
American papers on corundum. 
338 Natural and artificial abrasives. 
Ga, Geol. Surv., Bull. No. 2, pp. 119-133. 
Describes the character and occurrence of pumice, infusorial earth, 
tripoli, buhrstone, grindstones, oilstones, and whetstones. 
