184 
NATURE 
[ DECEMBER 20, 1906 
neighbourhood. Notwithstanding the presence of the genus 
Ptychomya, the affinities of its fauna clearly refer the 
Malone formation to the Jurassic system. New species of 
Perisphinctes, Olcostephanus, Nautilus, Trigonia, Natica, 
Nerinea, Nerinella, Martesia, Pholadomya, and others are 
figured and described. 
Bulletin No. 270+ contains records of borings and 
shallow excavations, with notes on the nature of the rock. 
From these data sectional elevations have been prepared 
traversing the district in many directions. Information of 
this kind, in the same handy form, would be of great 
value to engineers and contractors in the London area, as 
it is no doubt in New York. 
Bulletin No. 267° contains a short discussion of the 
problem of the classification and nomenclature of the 
great series of alternating magnesian limestones and sand- 
stones known as the ‘‘ magnesian series’’ or ‘‘ Ozark 
series ’? (Cambrian and Ordovician). The ore deposits do 
not appear to possess any striking features. 
A short description of the stratigraphy of the region 
(mainly Carboniferous), with particulars of the mineral 
resources, is given in Bulletin No. 256.° There is a 
coloured map. 
Taken together, Bulletins Nos. 247, 251, 263% give an 
1 
Fic. 2,—Land Erosion near Marin, N.C. Showing rapid erosion of soil 
by heavy rains when the forest cover is -reduced or destroyed. From 
“Southern Appalachian Forests.”’ 
excellent survey of the conditions of gold mining in Alaska. 
Nos. 247 and 251 deal with the geology of their respective 
districts; No. 263 contains a wealth of information upon 
all the subjects that fall within the scope of the title, and 
no miner should venture to Alaska without a copy. All 
three bulletins are well illustrated. 
A more generalised account of the same region is con- 
tained in ‘‘ The Geography and Geology of Alaska,’’ by 
A. H. Brooks (Professional Paper No. 45, 19065). This 
1 Bulletin No. 270, ‘‘ The Configuration of the Rock Floor of Greater 
New York." By W. H. Hobbs. (r90s.) 
2 Bulletin No. 267. ‘‘The Copper Deposits of Missouri.” By H. O. 
Foster Bainand E. O. Ulrich. (1905.) 
% Bulletin No. 256. ‘‘ Mineral Resources of Elders Ridge Quadrangle, 
Pennsylvan a.” By R. W. Stone. (1905.) 
4 Bulletin No. 247. ‘The Fairhaven Gold Placers, Seward Peninsula, 
Alaska. By F. H. Moffit. (x905.) Bulletin No. 251. ‘The Gold 
Placers of Forty-mile, Birch Creek and Fairbanks Regions, Alaska.” By 
L. M. Prindle. _(1905.) Bulletin No. 263. ‘* Methods and Costs of Gravel 
and Placer Mining in Alaska.” By C. W. Purington. (1905.) 
5 Professional Paper No. 45. ‘‘ The Geograph d Geol f Alaska.” 
B A. H. Brooks. (1906.) ae a 
NO. 1938, VOL. 75 | 
well-illustrated volume deals with the climate, the drainage, 
the history of explorations and surveys, and the geology. 
In the last-named section an elaborate table is provided 
giving the correlation of the strata in the western United 
States and Canada. A bibliography is appended. 
Professional Paper No. 41* contains a good deal of 
useful information upon the mineral resources of the 
central copper region. There is also a short account of 
the voleanic rocks of Mount Wrangell and of the glaciation 
of the Copper River basin. There are numerous interest- 
ing illustrations. ‘ 
“The purpose of Mr. Alden’s paper’ is to throw, if 
possible, some fresh light on the relations which existed 
during the later stages of the Glacial epoch between the 
glaciers of south-eastern Wisconsin.’’ It is an interesting 
study of the phases of glaciation and deglaciation in an 
area of moderate size. he principal facts are graphically 
illustrated in a series of admirable maps, prepared by the 
author to show the relations of the several glacial deposits 
at different stages. 
Professional Paper No. 30. Parts of this volume* are 
excellent, but we are constrained to ask, For whom is it 
intended? Is it for the West Kentucky miner? Then why 
burden him with a dissertation on Carboniferous strati- 
graphy and paleontology? On the other hand, if it was 
meant for the help of palawontologists, why should their 
troubles be increased by recording new species under the 
title *‘ Lead, Zinc, and Fluorspar Deposits’’? As for the 
new species themselves, they may be found beautifully 
figured, but the diagnoses are very meagre. 
The bulk of Professional Paper No. 37* is a dreary mass 
of statistics relating to the forest conditions of southern 
Appalachia, but it contains a number of illustrations which 
will appeal to all who are interested in problems of afforest- 
ation and water supply. The forest suffers from ill-regu- 
lated lumbering and from fires, but far more damage is 
done, not to the forest alone, but to the water supply, the 
scenery, and the agriculture of large districts by the clear- 
ing of land for farm purposes on high ground and steep 
slopes. The rainfall on the north-western slopes ranges 
from 40 inches to 50 inches, on the south-eastern slopes 
from 60 inches to 70 inches, and heavy downpours are 
common. The two figures here reproduced bring out very 
clearly the cause of the trouble and one of its effects. 
In Professional Paper No. 38° is a careful description 
of the Bingham mining district, where low-grade copper 
and rich silver-lead ores occur in Carboniferous strata and 
in the later monzonite intrusions. 
Professional Papers Nos. 40 and 47° are two important 
paleontological works; both are illustrated with a large 
number of beautiful plates. 
It is not every mineral district that boasts of so elaborate 
a memoir as Professional Paper No. 427 within five years 
of its discovery. This paper deals with the geology, - 
petrology, faults, and veins, and gives details of each of 
the mines. The temperature in the Tonopah mines shows 
an abnormally rapid increase with depth, comparable fo 
that in the Comstock. 
In Professional Paper No. 49° a general account is 
given of the Cumberland Gap coalfield, Kentucky. All the 
rocks of this basin are of the age of the Pottsville group 
of the Pennsylvanian coalfield. The field has only been 
exploited since 1892; eight seams are mined at present; 
their thickness ranges from 4 feet to 6 feet. 
The Annual Report of the Geological Survey of Canada 
8 
1 Professional Paper No. 41. ‘‘ Geology of the Central Copper River 
Region, Alaska.” By W. C. Mendenhall. (1905 ) 
2 Professional Paper No. 34. ‘‘ The Delavan Lobe of the Lake Michigan 
Glacier.” By W. C. Alden. (1904 ) 
3 Professional Paper No. 30. ‘ The Lead, Zinc, and Fluorspar Deposits 
of Western Kentucky.” By E O. Ulrich and W. S. Tangier Smith. (1905.) 
4 Professional Paper No. 37. ‘‘The Southern Appalachian Forests.” 
By H. B. Ayres and W. W. Ashe. (1¢0--) é 
5 Professional Paper No. 38 “Economic Geology of the Bingham 
Mining District, Utab.”" | By J. M. Boutwell and others. (1g05.) 
6 Professional Paper No. qo. ‘The Triassic Cephalopod Genera ‘or 
America.” Ry A. Hyatt and J. P. Smith. (1905.) Professional Paper 
No. 47- ‘‘The Tertiary and Quaternary Pectens of California.” By 
R. Arnold. (1906 ) 
7 Professional Paper No. 42. ‘‘ Geology of the Tonopah Mining District, 
Nevada” By J. E. Spurr. (1905 ) 
8 Professional Paper No. 49. ‘‘ Geology and Mineral Resources of Part 
of the Cumberland Gap Coalfield, Kentucky." By G. H. Ashley and 
L. C. Glenn. 
