weeks.] PALEONTOLOGY, PETROLOGY, AND MINERALOGY, 1890. 91 
724 Weed (Walter Harvey) and Firsson (Louis V.). The Bearpaw 
Mountains, Montana. [Part l.J 
Am. Jour. Sci., 4th ser., vol. i, pp. 283-301 and 351-362, figs. 1-1 ; vol. ii, 
pp. 136-148, 1896. 
Describes the topography and geology of the region and the character 
and distribution of the extrusive and intrusive rocks. Describes the 
petrographic character, and chemical composition of the several rock 
types of an intrusive igneous mass, differentiated in place, including 
quartz syenite, yogoite, shonkinite, augite-syenite, trachyte, nepheline 
basalt, and leucitite. Compares the differentiation at this locality with 
that at Yogo Peak, Montana. 
725 Bearpaw Mountains of Montana. [Part II.] 
Am. Jour. Sci., 4th ser., vol. ii, pp. 188-199, figs. 3-5, 1896. 
Describes the occurrence of the tinguaite dikes and the petrographic 
and chemical characters of the rocks. 
720 Missourite, a new leucite rock from the Highwood Mountains 
of Montana. 
Am. Jour. Sci., 4th ser., vol. ii, pp. 315-323, 1896. 
Describes the geologic occurrence, megascopic and microscopic char- 
acters and chemical analyses of the new rock type, Missourite. 
727 Geology of the Little Rocky Mountains [Montana]. 
Jour, of Geol., vol. iv, pp. 399-428, figs. 1-3, 1896. 
Describes the physiography of the region, the geologic structure and 
the lithologic character and distribution of the Cambrian, Siluro-Devo- 
nian, Jurassic, and Cretaceous rocks, and mentions the fossils collected. 
Describes the occurrence and petrographic character of the igneous 
rocks, including granite, porphyry, and phonolite. Gives a brief account 
of the occurrence of the gold and silver ores. 
728 Weeks (Fred Bougliton). Bibliography and Index of North 
American geology, paleontology, petrology, and mineralogy 
for 1892 and 1893. 
U. S. Geol. Surv., Bull. No. 130, 210 pp., 1890. 
Contains an authors' list of titles of papers and a subject index. 
729 Bibliography and Index of North American geology, paleon- 
tology, petrology, and mineralogy for the year 1894. 
U. S. Geol. Surv., Bull. No. 135, 141 pp., 1890. 
7,30 Bibliography and Index of North American geology, paleon- 
tology, petrology, and mineralogy for the year 1895. 
IT. S. Geol. Surv., Bull. No. 140, 130 pp., 1890. 
731 Weller (Stuart). [Review of the "Thirteenth Annual report of 
the State Geologist (New York) for the year 1893," by James 
Hall.] 
Jour, of Geol., vol. iv, pp. 110-119, 1890. 
732 [Review of "Neocene Mollusca of Texas, or fossils from the 
deep well at Galveston," by G. D. Harris.] 
Jour, of Geol., vol. iv, p. 126 (12 1.), 1890. 
