578 



SCIENCE. 



[N. S. Vol. V. No. 119. 



as the dissected remains of a group of Ter- 

 tiary volcanoes. Seen from the surround- 

 ing plains, the mountains have a serrate 

 outline, highest near the center of an oval 

 area, 20 by 40 miles in diameter. Seen in 

 plan, they exhibit a well defined system of 

 radial valleys. The interstream peaks and 

 ridges consist of volcanic tuffs, breccias, and 

 flows, lying on Cretaceous strata, around 

 a central district of laccolitic cores, dikes 

 and bosses. The Cretaceous strata are 

 somewhat upturned and baked around the 

 largest laccolitic mass, and the ' contact 

 ring ' stands in bold relief, forming ridges 

 around the igneous center. 



In the absence of detailed surveys of this 

 region, a somewhat similar type may be 

 studied on the topographical and geological 

 maps of the great dissected volcano, known 

 as the Cantal, on the central plateau of 

 France. 



LAtTEENTIAN HIGHLANDS OF CANADA. 



A REPORT by Professor F. D. Adams on 

 the geology of a portion of the Laurentian 

 area (Geol. Surv. Canada, VIII., 1S96, pt. 

 J) includes a brief account of the physical 

 features of an area lying northwest of 

 Montreal. Leaving the drift-covered val- 

 ley of the St. Lawrence, underlain by 

 paleozoic strata, the Archaean highlands 

 rise abruptly in a line of hills, which con- 

 stitute the edge or southerly limit of a 

 great uneven plateau, gradually rising to 

 the northwest. Its surface is undulating 

 or mammilated; the depressions being gen- 

 erally filled in with drift, forming extensive 

 flats, studded with numerous lakes, great 

 and small. Eounded, ice-worn bosses or 

 hills protrude through the drift, seldom ris- 

 ing more than three or four hundred feet 

 above the general level, and presenting, 

 especially when burnt over, great faces or 

 whole summits of bare rock. The lake 

 outlets have carved terraces in the drift- 

 clogged valleys. Settlements are scattered 



over the drift plains, avoiding the rocky 

 hills. 



The ' date of origin of the undulating 

 plateau is not considered ; but Lawson's 

 supposition that it is a pre-paleozoic land 

 surface, long preserved by burial, and lately 

 revealed by the erosion of its cover — a 

 geographical fossil, as it were — seems to be 

 contradicted by the well defined line of 

 blufis in which the Archaean rises from the 

 St. Lawrence valley, unless this line is de- 

 termined by an unmentioned fault. 



MAPS OF MT. DESERT. 



Messrs. Bates, Rand and Jaques have 

 rendered a service to the summer residenta 

 of Mt. Desert by publishing several good 

 maps of the island ; one on a scale of 

 1:40,000 (in a single sheet or folded in 

 cover), another on a scale of 1:25,000 in 

 two large sheets, and a third of Bar 

 Harbor, on a still larger scale. All have 

 contour lines, the first two printed in 

 brown with the culture in the black and 

 the water in blue. A special map of the 

 eastern part of the island shows the moun- 

 tain paths in red. All the maps are based 

 on the Coast Survey sheets ; but the names 

 are carefully revised to accord more closely 

 with local usage, the revision and republi- 

 cation being the outcome of a careful work 

 on the Flora of Mt. Desert by Mr. E. L. 

 Rand and collaborators. Any of the maps 

 can be had of Mr. Waldron Bates, 40 Water 

 street, Boston. To the more observant of 

 the island residents, winter or summer, 

 these maps would serve as a good base for 

 detailed record of the supposed high-level 

 shore lines, described by Shaler. 



W. M. Davis. 

 Harvard University. 



CURRENT NOTES ON ANTHROPOLOGY. 

 THE PROGRESS OF ANTHROPOLOGY. 



The President of the Anthropological In- 

 stitute of Great Britain, Mr. E.W. Brabrook, 

 in his annual address in January last, re- 



