30 BIBLIOGRAPHY AND INDEX OF N. A. GEOLOGY, [bull. 162. 
156 Clarke ( John M.). Notes od some crustaceans from the Chemung 
group of New York. 
N. Y., 15th Ann. Rept. State Geologist, vol. i, pp. 729-738, figs. 1-4, 
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1898. 
Describes Pephricaris horripilata n. sp., and Bronteus senescens 
Clarke. 
157 Claypole (E. W.). Microscopical light in geological darkness. 
Am. Geol., vol. xxii, pp. 217-228, 1898. 
Describes the use of the microscope in the study of geologic phe- 
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158 Glacial theories, cosmical and terrestrial. 
Am. Geol., vol. xxii, pp. 310-315, 1898. 
Discusses various hypotheses. 
159 Clements (J. Morgan). A study of some examples of rock vari- 
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160 Clendenin (W. W.). Clays of Louisiana. 
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Describes the occurrence and character of the clays of the State. 
161 Coleman (Arthur P.). Clastic Huronian rocks of western Ontario. 
Geol. Soc. Am., Bull., vol. ix, pp. 223-238, 1 fig., 1898; Abstracts 
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Discusses the classification of the series and describes the Huronian 
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162 Glacial and interglacial deposits at Toronto [Canada.] 
Brit. Assoc. Adv. ScL, Rept., 1897, pp. 650-651, 1898. 
Describes glacial phenomena of the vicinity. 
163 Notes on the western Ontario gold fields. 
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Describes the occurrence and character of the gold-bearing deposits. 
164 Cooper (A. S.). A bituminous rock deposit in Santa Barbara 
County, California. 
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Describes the geology of the region and the occurrence of the bitu- 
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165 Southern California petroleum. 
Mg. and Sci. Press, vol. lxxvii, p. 372, 2 figs., 1898. 
Describes occurrence of petroleum in Santa Barbara County, Cali- 
fornia. 
