Geology and Natural History. 461 
not @ reprint, as was then supposed. The present issue, by Mr. Lea 
of Philadelphia, is an American reprint of the same English edi- 
tion, and so far as we have compared the two there is no verba 
IL GroLoey anp Narurat History. 
1. Contributions from the Laboratory of the University of 
ia. No. 1. 
Pennsylva Corundum, its alterations and associa ed 
minerals ; A, GE 6 8v From the Proceedings 
and relation of the chrysolite of the region, and shows that it 1s true 
chrysolite, and not a hydrous mineral allied to villarsite, as made 
out by Prof. C. U. Shepard ; and that it is only sometimes hydrous 
i y himself of spinel, 
site and lesleyite, paragonite, jefferisite. chlorite of different kinds, 
attersonite (shown to be near thuringite), chloritoid, margarite, 
esides descriptions and analyses of the new chlorite-like mine- 
rals kerrite, maconite, willeowite and the margarite-like species 
- Hunt’ at ; j 
beauxite), gibbsite (probably), opal, zoisite, tourmaline (in all 
probability), jidrolite, cyanite, damourite, staurolite (probably), 
pyrophyllite, ephesite and lesleyite (which are shown to be mix- 
tures containing a large percentage of free corundum, confirming 
Prof, Brush’s results), paragonite, euphyllite, jeferisite, chlorite, 
pattersonite, chloritoid, margarite, lazulite. Dr. Genth concludes 
as follows : 
