412 Scientific Intelligence. 



the report, showing the positions of mines, hot springs, and gen- 

 eral features of the country, and also give the courses of a num- 

 ber of anticlines in the stratified rocks. The course on the 

 map for the principal system of anticlines is about N 75° E, and 

 for another, in Garland Co., less prominent about 1ST 20° E. The 

 interesting fact is brought out that black shales and earth in 

 Garland, Montgomery, Hot Spring and Polk counties, in which 

 thermal springs formerly existed, contain much graphite, and 

 that the graphitic earth is used in paint manufacture. The valu- 

 able report closes with a list of the minerals in central western 

 Arkansas. This first volume is to be followed by three others : the 

 second, by Prof. R. T. Hill, on the Mesozoic geology; the third, 

 by Mr. A. Winslow, on the geology of a part of the Coal re- 

 gions; and a fourth, to consist of reports on Little Rock, Magnet 

 Cove and other localities, besides a chemical and a topographical 

 report. 



3. The Cretaceous and Tertiary Geology of the Sergipe- 

 Alagdas basin of Brazil ; by John C. Branner, Ph.D. pp. 369 

 to 434 of vol. xvi of Trans. Amer. Phil. Soc, 1889, with Plates I 

 to V. — This valuable memoir by Dr. Branner is based on obser- 

 vations made by him in the years 1875, 1876, while assistant 

 geologist in the Geological Survey of Brazil. The author favors 

 the view that the Mesozoic rocks of the region are Cretaceous, 

 and identical with the coastal Cretaceous, opposing the view of 

 Mr. Derby. The Tertiary sand-beds are described as in part 

 changed to quartzyte ; not by ordinary metamorphic methods, 

 but as a result of weathering or through the action of the rains 

 and heat of the climate. The solid " glassy quartzyte " in some 

 places projected out in blocks, when but a few feet within the 

 material was only sand partially consolidated, and in the interval 

 the firmness increased toward the surface. 



4. Tertiary Volcanoes of the Western Isles of Scotland. — 

 Prof. J. W. Judd has a notice of Dr. Geikie's memoir on this 

 subject in the Geological Magazine for February, on p. 91. He 

 refers to the views in his paper of 1874, on the Ancient Volcanoes 

 of the Highlands, and states that while Dr. Geikie agrees with 

 him in several of his conclusions, he does not in two, he holding 

 (1) that the ejection of the "felstone" lavas and the intrusion 

 of the granites preceded the appearance of the basalts and 

 gabbros ;" and (2) " that the five centers of eruption mark the 

 sites of as many great volcanic cones now ruined and dissected 

 by denudation." In opposition to the latter view, Dr. Judd 

 pointed out in his paper, as he states, " that the numbers and 

 dimensions of the Tertiary dykes are not such as would warrant 

 us in inferring that they formed the conduits through which the 

 enormous masses of lava forming the plateaus were erupted ; and 

 the absence of all proofs of contact-metamorphism at their sides, 

 and of evidence that the majority of them ever reached the 

 surface at all was commented on." He adds that in " 1874 he 

 further pointed out that some of these dykes appear to mark the 



