weeks.] PALEONTOLOGY, PETROLOGY, AND MINERALOGY, 1904. 69 
Irving (flohn Duer) — Continued. 
3. Microscopic structure and origin of certain stylolitic structures in 
limestone. 
Abstract: Am. Geol., vol. 33, pp. 266-267, 1904; Science, new ser., vol. 19, p. 
580, 1904. 
Discusses the character and origin of stylolites. 
Irving (John Duer) and Emmons (S. F.). 
1. Economic resources of the northern Black Hills. Part II. Mining- 
geology. 
U. S. Geol. Surv., Professional Paper no. 26, pp. 43-222, 19 pis., 11 figs., 1904. 
Describes the character, occurrence, and geologic relations of the gold, silver, 
copper, tin, and tungsten ores, and their economic development. 
Ishikawa (S.). 
1. Latest eruption of Colima volcano, Mexico. [In Japanese.] 
Tokyo Geol. Soc, Jour., vol. 11, pp. 9S-103, 1904. 
J. 
Jackson (Robert T.). 
1. Charles Emerson Beecher. 
Am. Nat., vol. 38, pp. 407-426, 1 pi. (por.), 1904. 
Gives an account of his life and work, and a list of his published papers. 
Jacobs (E.). 
1. The coal fields of Crow's Nest Pass, British Columbia. 
Eng. Mag., vol. 27, pp. 36-57, ill., 1904. 
Describes the location of the field, the occurrence of the coal, and the mining 
operations. 
Jaggar (Thomas Augustus, jr.). 
1. Economic resources of the northern Black Hilts. Part I. General 
geology. 
U. S. Geol. Surv., Professional Paper no. 26, pp. 13-41, 1 pi., 5 figs., 1904. 
Describes topography, stratigraphy, lithology, geologic structure, and char- 
acteristic sections. 
- 2. The eruption of Mount Pelee, 1851. 
Am. Nat., vol. 38, pp. 51-73, 1904. 
Translated from the French of LePrieur, Peyraud and Rufz. 
3. The initial stages of the spine on Pelee. 
Am. Jour. Sci., 4th ser., vol. 17, pp. 34-40, figs. 1-3, 1904. 
Describes occurrence and appearance of spines in the crater of Mont Pele and 
gives an explanation of their origin. 
4. The eruption of Pelee, July 9, 1902. 
Pop. Sci. Monthly, vol. 64, pp. 219-231, figs. 1-3, 1904. 
Gives details of observations on the eruption of July 9, 1902, and discusses 
the causes of the phenomena. 
Jeffrey (Edward C). 
1. A fossil Sequoia from the Sierra Nevada. 
Bot. Gaz., vol. 28, pp. 321-332, 1904. 
