168 BIBLIOGRAPHY OF NORTH AMERICAN GEOLOGY, 1906-1907. 
Sellards, E. H. — Continued. 
2168. Types of Permian insects. — Am. Jour. Sci., 4th ser., vol. 22, pp. 249- 
258, 8 figs., September, 1906. 
Discusses the characters and classification of the Odonata, describing particularly Tupus 
permianus new genus and species. 
2169. Types of Permian insects. Part II. — Am. Jour. Sci., 4th ser., vol. 23, 
pp. 345-355, 13 figs., May, 1907. 
2170. Occurrence and use of artesian and other underground water. — Florida 
Agric. Exp. Station, Bull. no. 89, p. 87-113, 3 figs., March, 1907. 
2171. Florida State Geological Survey, organization and plans, 1907. 11 pp. 
2172. Venation of the wings of Paleozoic dragon-flies. — Abstract: Science, 
new ser., vol. 25, pp. 731-732, May 10, 1907. 
2173. Origin of sink-holes. — Science, new ser., vol. 26, p. 417, September 27, 
1907. 
2174. Notes on the spore-bearing organ Codonothcca and its relationship 
with the Cycadofilices.— New Phytologist, vol. 6, pp. 175-178, 1 fig., 1907. 
Shaler, Millard K. 
2175. Gypsum in northwestern New Mexico. — U. S. Geol. Survey, Bull. no. 
315, pp. 260-265, 1 fig., 1907. 
2176. A reconnaissance survey of the western part of the Durango-Gallup 
coal field of Colorado and New Mexico. — U. S. Geol. Survey, Bull. no. 316, pp. 
376-426, 2 pis., 1907. 
Shaler, Millard K., and Gardner, James Ff. 
2177. Clay deposits of the western part of the Durango-Gallup coal field 
of Colorado and New Mexico.— U. S. Geol. Survey, Bull. no. 315, pp. 296-302, 
1907. 
Shamel, Charles H. 
2178. Do the geological relations of ore deposits justify the retention of the law 
of the apex? — Econ. Geology, vol. 2, no. 1, pp. 62-77, 4 figs., 1907. 
2179. Mining, mineral, and geological law. New York, Hill Publishing Com- 
pany, 1907. 627 pp., 101 figs. 
Shannon, Charles W. 
2180. The drainage area of the east fork of White River [Indiana]. — In- 
diana Acad. Sci., Proc, 1906, pp. 53-70, 1 pi., 20 figs., 1907. 
Includes an account of the geology of the area. 
2181. The iron-ore deposits of Indiana. — Indiana, Dept. Geol. and Nat. Res., 
31st Ann. Rept, pp. 299^28, 18 pis., 7 figs., 1907. 
Iron ores of Martin County, Indiana. — See Beede and Shannon, no. 182. 
Sharwood, W. J. 
2182. Some associations of gold with pyrite and tellurides. — Min. and Sci. 
Press, vol. 94, pp. 117-119, 11 figs., January 26, 1907. 
2183. Gold tellurides.— Min. and Sci. Press, vol. 94, pp. 731-732, 4 figs., 
June 8, 1907. 
Describes the occurrence of gold ores at Goldfield, Nevada. 
Shattuck, George Burbank. 
2184. The Pliocene and Pleistocene deposits of Maryland. — Maryland Geol. 
Survey, Pliocene and Pleistocene, pp. 21-137, 31 pis., 9 figs., 1906. 
Reviews previous work bearing upon the subject, with a bibliography, describes the 
general stratigraphic relations and physiography, the character, distribution, and rela- 
tions of Pliocene and Pleistocene formations, and the geologic history of the region. 
