May 7, 1697.] 



SCIENCE. 



723 



rock plains of Sonora are only veneered 

 with gravel and sand. At the outlet of 

 mountain ravines McGee pictures and de- 

 scribes triangular, convex ' fans,' which are 

 really carved in solid rock like the plains, 

 and only veneered with alluvium. These 

 must be retreating alluvial fans, in con- 

 trast to the advancing alluvial fans ordi- 

 narily seen in mountain valleys. After ad- 

 vancing for a time, fans of the latter class 

 are often dissected by streams and thus 

 worn away; but the Sonoran rock-fans 

 seem to have been worn back by sheetflood 

 action, thus preserving their form. 



BELIEF MAP OF NEW JERSEY. 



A HANDSOME and effective publication of 

 the New Jersey Geological Survey is a new 

 relief map of the State, on a scale of four 

 miles to an inch. It is shaded in gray- 

 brown, as if under northwest illumination, 

 making the relief of the surface only too 

 clear. The map will prove extremely ser- 

 viceable, but it may be questioned whether 

 a more delicate rendering would not have 

 been more educative, particularly in the 

 schools, where such a map as this must 

 have its greatest and most important use. 

 This is particularly the case in the southern 

 part of the State, where the shading does 

 not seem to be reduced to the delicacy of the 

 faint inequalities in the surface, but where 

 the inequalities of the surface are exagger- 

 ated to meet the demands of distinct shad- 

 ing and easy recognition. The effect pro- 

 duced by the southern plains does not 

 tally with that gained on reading the text 

 of the State Survey reports ; it is as if the 

 drawing of the relief map were done by a 

 topographer accustomed to exaggerated sec- 

 tions on which an almost imperceptible 

 natural slope becomes a distinct incline, 

 rather than by a geographer who wished to 

 give a just sense of the proportions of hills 

 and plains. The criticisms directed against 

 the vertical exaggeration of geographical 



models may be equally directed against so 

 forcible a relief map as this. The map is 

 headed with the names of John C. Smock, 

 State Geologist, and C. C. Vermeule, topog- 

 rapher; but no explicit recognition is given 

 to the artist who prepared the map or to 

 the lithographer who printed it. 



MORAINES OF THE MISSOURI COTEAU. 



A REPORT with the above title by J. E. 

 Todd forms Bulletin 144 of the U. S. Geo- 

 logical Survey. It is chiefly occupied with 

 detailed descriptions of the moraines, from 

 which one may gain a good idea of their 

 importance in determining the relief of the 

 Coteau. A map and many plates, appar- 

 ently drawn in outline from photographs, 

 afford good illustrations ; but it is often 

 difficult to identify localities between text 

 and map. The Blue lake loop, 60 miles 

 southeast of Bismarck, six to ten miles 

 wide, is so rough, with so many stony hills 

 and marshy hollows, as to present a for- 

 midable barrier to travel. One may easily 

 lose his way on this undulating surface, 

 where no conspicuous landmarks serve as 

 guides. Many of the moraines are traversed 

 by dry channels that once carried water 

 from the melting ice sheet. The channels are 

 now frequently occupied by small shallow 

 lakes. The Eee hills, 40 miles east of 

 Pierre, chiefly of Cretaceous beds with a 

 veneer of drift, are traversed by an elabo- 

 rate extinct drainage system ; the main 

 channel begins in a gap in the hills, receiv- 

 ing tributaries from either side on its way 

 south, and gaining a depth of 60 to 70 feet 

 with abrupt, stony sides, and a breadth of 

 f mile (p. 27). 



NOTES. 



The two numbers of Appalachia for 1896 

 contain several good accounts of mountain 

 ascents in the Canadian and Montana 

 Rockies and in the High Sierra of Califor- 

 nia. A number of the plates are excellent; 

 that of the Avalanche lake, Montana, being 



