vil CONTENTS. 
XXII.—Contributions from the Sheffield Laboratory of Yale Col- 
lege. No, XV. Observations on the native hydrates of Iron ; 
by ver J. ee 4 with _— of po by CHARLES 
. Rop - 219 
XXII. som a new Test for Hy nodithphitad by ML bas ee - 222 
XXIV.—Contributions to Chemistry from the Laboratory of the 
Lawrence Scientific School. No, 4.—On a new mineral from 
Rockport, Mass.; by W. J. Kxowzron, - 
XXV.—On the Subdivisions of the Cretaceous rocks of California : . 
by Wm. M. G ag eo i= ghee - - 
XXVI.—On a new Poets for technical our of Potroletm 
and kindred substances; by S. F. Pecxuam, . 
XXVII.—Notes on the Grass Valley Gold- ining District ty 
Prof. B. Siuumay, - 236 
XXVIII.—The Action of Sunlight on Chie: ; by wishin npoeees 244 
XXIX.—Crystallogenic and Cryitatlographic Contributions; by 
ames D, Dana— n a connection between Crystalline 
form and Chemical constitution, with some inferences there- 
from.—Supplement,- - ~ - 252 
.—Formie versus Carbonous acid ; ie one F. Barker, - 263 
XXXI.—Observations on Skylight Polarization in Nebraska dur- 
ing the month of July, 1867; by Eowarp O.Cuasz,- - 265 
SCIENTIFIC INTELLIGENCE. 
Chemistry and Physics.—On the synthesis of organic acids, Canrus, 265.—On the 
action of heat upon benzol and analogous ‘hydrocarbons, Bexraetor, 266.—On 
acids of the lactic series, Franxuanp and Durra, 268.—Thallic acid, E. Cans- 
TANJEN, 269.—The new Chemical Calculus of Sir Buysamin Bropie, 270. 
Mineralogy and Geology.—Notice of volume IV of the Paleontology of New York, 
273.—On the Paleontology of Victoria, South Australia, by Frepesicx MoCor, 
279.—Note by F. B. Meek to his Review of Prof. Geinitz in regard to Nebraska 
fossils, 282.—Note on me Corundophilite of Chester, Mass.: Note on the opti- 
cal characters of different micaceous minerals called Margarite, by Mr. DzsCuor- 
ZEAUX, 283. ocean: Ol Canadense in Fioland: Geological observations in Colo- 
rado: Geological Survey of Nebraska, 284 
Botany.—Manual of the Botany of the Northern United States, including the dis- 
trict East of the Mississippi and North Carolina and Tennessee, arranged accord- 
ing to the natural system, by Asa Gray, 284. 
Astronomy.—Recent Observations and Remarks of Hofrath 
Schwabe regarding 
Sun-spots and other Solar Phenomena, et a Meteor of July 18th, 1867, 
os asec 288. 
