weeks.] PALEONTOLOGY, PETROLOGY, AND MINERALOGY, 1904. 133 
Wright (Charles W.). 
1. The Porcupine placer mining' district, Alaska. 
IT. S. Geol. Surv., Bull. no. 225, pp. 60-63, 1904. 
Describes briefly the general geology and the occurrence and raining of placer 
gold. 
12. The Porcupine placer district, Alaska. 
U. S. Geol. Surv., Bull. no. 236, 35 pp., 10 pis., 4 tigs., 1904. 
Describes the general geology, the character and occurrence of placer gold 
deposits, and the mining operations. 
'Wright (Fred Eugene). 
1. Two microseopic-petrographical methods. 
Am. Jour. Sci., 4th ser., vol. 17, pp. 385-391, 6 figs., 1904. 
Describes methods of determining index of refraction and optical character of 
minerals. 
2. Der Alkalisyenit von Beverly, Massachusetts, U. S. A. 
Tschermak's Min. u. Petrogr. Mitt, N. F., Bd. 19, pp. 308-320, 11 figs., 1900. 
Describes crystallographic characters and composition of an alkali-syenite 
from Beverly, Massachusetts. 
Wright (G. Frederick). 
11. Evidence of the agency of water in the distribution of the loess in 
the Missouri Valley. 
Am. Geol., vol. 33, pp. 205-222, 3 pis., 1904. 
Discusses the distribution of the loess and the evidences of its deposition by 
the agency of water. Includes a note by Professor Lane on the flow of 
flooded rivers. 
2, Another Glacial wonder. 
The Nation, vol. 77, pp. 462-463, 1904. 
Describes the occurrence of Glacial boulders in the vicinity of Tuscumbia, Mo., 
and gives an explanation as to how they came there, and its bearing on the 
origin of the loess. 
Y. 
Yates (William). 
1. Natural history, meteorological and geological notes from Burford 
township [Ontario]. 
Hamilton Sci. Assoc, Jour. & Proa, no. 20, pp. 144-154, 1904. 
Includes observations upon glacial phenomena in this region. 
Yates (Lorenzo Gordin). 
1. Prehistoric California. 
So. Cal. Acad. Sci., Bull., vol. 3, pp. 6-10, 1 pi., 1904. 
Sec no. 1365 of U. S. Geol. Surv., Bull. no. 240. 
z. 
Zirkel (Ferdinand). 
p.. Ueber die gegenseitigen Beziehungen zwischen der Petrographie 
und ano-renzenden Wissenschaften. 
Jour. Geol , vol. 12, pp. 485-500, 1904. 
Discusses the scope and methods of petrography and relations to connected 
sciences. 
