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X X VIII. The Marquette Iron-Bearing District of Michigan, with Atlas, by ( '. R. Van Hi~(- and W. 
S. Bay ley, including a Chapter on the Kepnblic Trough, by H. L. Smyth. 1897. 35 pi. 
and ..tlas of 39 sheets folio. Price $5.75. 
XXIX. Geology of Old Hampshire County. Massachusetts, comprising Franklin. Hampshire, and 
Hampden Counties, by Benjamin Kendall Emerson. 1898. i°. xxi, 790 pp. 35 pi. Price $1.00. 
XXX. Fossil Medusa?, by Charles Doolittle "Walcott. 1898. 4°. ix, 201 pp. 47 pi. Price $1.50. 
XXXI. Geology of the Aspen Mining District. Colorado, with Atlas. by Josiah Edward Spurr. 1898. 
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XXXII. Geology of the Yellowstone National Park, Part II, Descriptive G oology, Petrography, and 
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Stanion. and F. H. Knowlton. 1899. 4°. xvii, 893 pp. 121 pi. Price $2.45. 
XXXIII. Geology of the Xarragansett Basin, by X. S. Shaler. J. B. Woodworth, and August F. 
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XXXJLV. The Glacial Gravels of -Maine and their Associated Deposits, by George II. Stone. 1899. 
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XXXV. The Later Extinct Floras of North America, by John Strong Newberry ; edited by Arthur 
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XXXVI. The Crystal Falls Iron-Bearing District of Michigan, by J. Morgan Clements and Henry 
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duction by Charles Richard Tan Hise. 1899. 4°. xxxvi, 512 pp. 53 pi. Price $2. 
XXXVII. Fossil Flora of the Lower Coal Measures of Missouri, by David White. 1899. 4'. xi, 
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XXXVIII. The Illinois Glacial Lobe, by Frank Leverett. 1899. 4°. xxi. 817 pp. 24 pi. Price $1.00. 
XXXIX. The Eocene and Lower Oligocene Coral Faunas of the United States, with Descriptions of 
a Few Doubtfully Cretaceous Species, by T. Wayland Taughan. 1900. 4°. 263 pp. 24 pi. Price 
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XL. Adephagous and Clavicorn Coleoptera from the Tertiary Deposits at Florissant, Colorado, with 
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In preparation : 
< — Flora of the Laramie and Allied Formations, by P'rank Hall Knowlton. 
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