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742 Todd (flames E.). Some problems of the Dakota artesian system. 
Abstract: Science, new ser., vol. 14, p. 794, 1901. 
Sci. Am. Suppl, vol. 52, p. 21504, 1901. 
743 Moraines and maximum diurnal temperature. 
Abstracts: Science, new ser., vol. 14, pp. 794-795, 1901. 
Sci. Am. Suppl., vol. 52, p. 21504, 1901. 
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744 Turner (Henry W.). The geology of the Great Basin in eastern 
California and southwestern Nevada. 
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vol. 12, p. 498 (| p.), 1901. 
Describes the structure of the region and its general stratigraphic 
features. 
745 Perknite (lime-magnesia rocks). 
Jour. Geol., vol. 9, pp. 507-511, 1901. 
Describes the character and occurrence of a new rock type and gives 
chemical analyses of rocks included in this group. 
746 - - The mines of Esmeralda Count}^, Nevada. 
Mg. and Sci. Press, vol. 82, pp. 73-74, 1901. 
Contains notes on the general geology of portions of the County. 
747 Tyrrell (J. B.). Report on the east shore of Lake Winnipeg and 
adjacent parts of Manitoba and Keewatin, compiled by 
D. B. Dowling. 
Can. Geol. Surv., new ser., vol. 11, Rept. G., 96 |>i>., i! pis., L901, pub- 
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u. 
748 Udden (J. A.). Geology of Louisa County [Iowa]. 
Iowa Geol. Surv., vol. 11, pp. 58-126, pi. 4, fig. 1, 2 maps, 1901. 
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products. 
749 Geologie of Pottawattamie County [Iowa]. 
Iowa Geol. Surv., vol. 11, pp. 202-277, pi. 6, figs. 13-15 and map, 1901. 
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boniferous, Cretaceous, and Pleistocene strata and the occurrence of 
"" economic products. 
750 Ulrich (E. ().). Systematic paleontology. Eocene Arthropoda. 
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751 Eocene Molluseoidea (Bryozoa). 
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