Geology and Natural History. 59 
The plates illustrating the brief reports of Dr. Hayden are ex- 
cellen 
Among the results of the same expedition, under the Interior 
Department, there have recently appeared also—(1.) A “ Prelim- 
inary map of Central Colorado,” showing the region surveyed in 
1873 and 1874; Primary triangulation by G. T . Gardner, topogra- 
phy by G. R. Bechler , H. Gannett, A. O. Wilson and §. B. Ladd. 
2.) A colored Geological map "ck the sources of the Snake River 
with its tributaries, and of portions of the headwaters of the Yel- 
lowstone, by G..R. ’ Bechler, topographer, and Frank H. Bradley, 
geologist. 
Ah) A colored Geological map of part of Montana and Wyo- 
Territories, embracing most of the country drained by the 
Seles: Gallatin and estar Yellowstone sian Geology by 
Hayden, assisted by A. C. Peale; dra wn by H. Gannett 
m notes and sketches by A. Burek, chief €* ety se of the 
Talewitons division. It has contour lines. 
“B.” On the ran of Pemnestiank GENTH. 
With an Appendix on the Hydro-carbon Conipomas, ‘by S. 
ADTLER; 206 vo Hartialnis , 1875.—Dr. Genth has in- 
etail the description of the localities in the State. Dr. Genth 
=a also a large number of new analyses recently executed 
y 
Report “J.” On the Petroleum of Pennsylvania, by Hunt 
Wricrey. With a map and profile of a line of levels hieeal 
Butler, Armstrong, and Clarion Counties, wt D. Ji: Lueas; also. a 
similar profile along sag bat Rock Creek, by J. P. Lesley. 
122 pp. 8vo. Harrisburg, 1875.—Mr. Wrigley treats of his sub- 
ject in all its bearings, historical, geographical, geological and 
economical; his report will be found of great value by all in- 
terested in the subject. 
eport upon the Reconnaissance of Northwestern —— 
ineluiling Yellowstone National Park, ste in the er of 
1873; by Wm. A, Jones, Captain of Engine rs U.S. A. 326 pp- 
Ren Aye numerous maps.—This v ee me consists = a General 
‘bat an Philelog al ‘he 0 coverin 200 pages, by Prof, T. B. 
shale a oat Min rt ving. 2 P Ei 
C. L. Herzmann ; a Botanical Report reed Dr. ©. C. Parry, and an 
