weeks] PALEONTOLOGY, PETROLOGY, AND MINERALOGY, 1901. 7{) 
709 Smith (George Otis) and Willis (Bailey). The Clealum iron ores, 
Washington. 
Am. Inst. Mg. Engrs., Trans., vol. 30, pp. 356-366, 1 fig., L901. 
Describes the character, occurrence and origin of the ores and the 
general geologic and structural feature of the region. 
710 Smith (James Perrin). The border line between the Paleozoic 
and Mesozoic in western America. 
Jour. Geol., vol. 9, pp. 512-521, 1901. 
Discusses briefly the criteria by which geologic time divisions of the 
line between this Paleozoic and Mesozoic as influenced by the faunas of 
certain beds of Idaho and California and their relation to allied Asiatic 
and European faunas. 
711 and Weller (Stuart). Prodromites, a new ammonite o-enus 
from the Lower Carboniferous. 
Jour. Geol., vol. 9, pp. 255-268, pis. 6-8, 1901. 
Discusses the occurrence of ammonites in upper Paleozoic rocks of tin- 
Mississippi Valley, and describes a new genus and two new species. 
71'2 Smock (John C). Administrative report. (New Jersey Geo- 
logical Survey.) 
N. J. Geol. Surv., Ann. Kept, for 1900, pp. xi-xl, 1901. 
Gives an account of the work of the Survey for the year, and dis- 
cusses the character and relations of the surface formations of southern 
New Jersey. 
713 Smyth (C. H., jr.). Geology of the crystalline rocks in the vicin- 
ity of the St. Lawrence River. 
N. Y. State Mus., 53d Ann. Kept., vol. 1, pp. rS5-rl04, pis. 13-24 and 
geologic map, 1901. 
Describes the gneiss and associated rocks of the region. 
714 Sollas (W. J.). Evolutional geology. 
Smith. Inst., Ann. Kept. 1900, pp. 289-314, pi. 1, 1901. 
715 Spalding (E. P.). The quicksilver mines of Brewster County, 
Texas. 
Eng. & Mg. Jour., vol. 71, pp. 749-750, figs. 1-6, 1901. 
Contains notes on the character and occurrence of the ore. 
716 Spencer (Arthur C). The iron ores of Santiago, Cuba. 
Eng. & Mg. Jour., vol. 72, pp. 633-634, 6 figs., 1901. 
Describes the character and geologic relations of the ore bodies. 
717 The physiography of the Copper River basin, Alaska. 
Abstract: Science, new ser., vol. 13, p. 189, 1901. 
Contains abstract of paper read before the Geological Society of Wash- 
ington. 
718 See Cross (Whitman), 176. 
719 Spencer (Joseph William Winthrop). On the- geological and 
physical development of Antigua. 
London GeoL Soc, Quart. Jour., vol. 57, pp. 490-505, and map, 1901. 
