weeks.] PALEONTOLOGY, PETROLOGY, AND MINERALOGY, 1901. 87 
259 Ells (R. W.). The Devonian of the Acadian provinces. 
Can. Rec. Scl, vol 8, pp. 335-343, L901. 
Reviews previous geologic work on the Devonian strata of the r< \ 
and discusses the problems involved. 
260 Ancient channels of the Ottawa River [Canada]. 
Ottawa Nat., vol. 15, pp. 17-30, 1 map, 1901. 
Describes glacial phenomena of the region. 
261 Emmons (Samuel Franklin). The secondary enrichment of ore 
deposits. 
Am. Inst. Mg. Engrs., Trans., vol. 30, pp. L77-217, L901. 
Discusses the process of the secondary enrichment of sulphide ore 
bodies by transference and reconcentration of the alteration products of 
the original vein materials by descending surface waters and the chem- 
ical reactions which take place. Describes the author's observations in 
various mining districts and discuss* s their hearing on these problems. 
262 Notes on two desert mines in southern Nevada and Utah. 
Abstract: Science, new ser., vol. 13, pp. 426-427, ©01. 
Contains abstract of paper read before the Geological Society of 
Washington. 
F. 
263 Fairbanks (Harold W.). Notes on the geology of the Three 
Sisters, Oregon. 
Abstracts: Jour. Geol, vol. 9, p. 73 (fp.), L901. 
Ge.ol.Soc. Am., Bull, vol 12, pp. 498 499 (j p.), 1901. 
Brief notes on occurrence of volcanic rocks. 
264 Pyramid Lake, Nevada. 
" Pop. Sci. Mo., vol. 58, pp. 405-514, figs. L-8, L901. 
Describes the geological history of the lake and adjacent region and 
the characteristics of the volcanic materials. 
265 Fairchild (Herman LeKoy). Beach structure in Medina sandstone. 
Am. Geol, vol 28, pp. 9-14, pis. ii-iv, L901. 
Review, Jour. Geol, vol. 9, pp. 549-550, 1901. 
Discusses the evidences indicating the origin of the ripple marks 
the Medina sandstone of New York. 
266 Farnsworth (P. -1.). When was the Mississippi Kiver Valley 
formed '{ 
Am. Geol, vol. 28, pp. 393-396, 1901 
Discusses the geologic history of the region. 
267 Farrington (Oliver Cummings). On the nature of the metallic 
veins of the Farmington meteorite. 
Am. Jour. Scl, 4th ser., vol 11, pp. 60-62, fig. 1,1901. 
268 The structure of meteorites. 7.111901 
Jour. Geol, vol. 9, pp. 51 66, figs 1-6 pp. 174 190 figs l I . ■ ■ 
Describes the various structural features ol meteontesanddi.cn 
their origin. 
