316 Scientific Intelligence. 
majority—where the age of beds has been determined solely by 
the comparison of land or fresh-water animals or plants with those 
found in distant parts of the globe, that such determinations are 
incorrect. 
6. The Geology of Minnesota, vol. I of the Final Report; 
N. H 
100 to 200 and sometimes 300 feet thick. The geology of the 
State hence is relatively simple. The chapter on building stones 
is the result of a careful study of the rocks, which included trials 
of strength besides ordinary and chemical analyses, the former by - 
Professor J, A. Dodge, the latter by the same and his assistant 
Mr. C. F. Sidener. Four syenytes: 1. from Sherburne Co., 2 
Beaver Bay Lake Co., 3, 4. Watab, Benton Co., afforded : 
SiO, #0; FeO; MgO CaO K,0 Na,O0 
1. Gray syenyte... 65°12 16°96 469 199 477 218  3°07= 98°78 
2. Red syenyte.... 71°81 12°82 602 056 226 251 1:92= 97°90 
‘ 3°06 593 162 «=: 2'-45= 99°68 
4. Red syenyte.... 78:12 1114 2°68 tf. 062 448 3:33=100°97 — 
The chapters on the geology of the counties are illustrated by 
detailed maps. The noted locality of red pipestone of the 
> 
tory and description of it are given by Professor Winchell. The 
pipestone is a bed of indurated clay in the red quartzyte of the 
region. 
7. Tertiary Geology of the Eastern and Southern United 
States.—Protessor A. Heilprin’s paper on this subject, noticed in 
volume xxiv of this Journal (1882), on page 228, is published in 
full in the Journal of the Academy of Natural Sciences of Phila- 
delphia, Part I of vol. ix (1884), : 
8. On the Development and Generic relations of the Corals of 
the Carboniferous System of Scotland; by Mr. Jamus THOMSON, 
.G.S. 208 pp. 8vo, with 14 plates. Read before the Philosoph- 
ical Society of Glasgow, March 14th, 1883.—This memoir 
