1268 Recent Literature. [ December, 
amount of animal life which can be sustained upon a small area, 
under suitable conditions, can only be understood by those who 
have dredged near the hundred fathom line on the west coast of 
the great Florida plateau. The dredge not unfrequently brings 
up large fragments of modern limestone, consisting of the dead 
carcasses of the species now living on the top. 
The Challenger and Tuscarora soundings have shown the ex- 
istence of submarine elevations of volcanic. origin, forming exten- 
sive banks, serving as foundations for barrier reefs and atolls, and 
wherever such plateaux reach, on their windward side, a level at 
which corals prosper, there coral reefs spring up and flourish. 
At lower levels are plateaux where mollusks, corals, echinoderms, 
etc., find the materials necessary for their coverings, These 
submarine beds of modern limestone lie in the very track of the 
ocean currents, and gain from them the carbonate of lime they 
require. Murray’s experiments seem to prove that this amounts 
to sixteen tons for every square mile a hundred fathoms dee 
The foundation for a coral reef is formed by the accumulation 
limestone and other animal remains upon an early fold of > 
earth’s crust, or upon a volcanic plateau, and corals do not encrus — 
the surface until the bank has risen to their bathymetrical limit. 
Thus the deposition of animal débris comes in as a SUP 3 
to elevation and subsidence, which alone were taken note | PY 
the theory of Darwin and Dana, and accounts for the per 
plateaux in regions where there has been little or no ¢ gi oe 
level from other causes, to a height favorable for the grow!” 
reef-building corals. ag > 
Grorr’s MıneraL ANatysts.—This is a series of one hundre 
ey fill out under thè 
octavo pages giving blanks for the student to f mines 
different physical characters and chemical reactions 0 sy she 
ey are conveniently arranged and accompanied by a athe a 
of terms most commonly used in describing minerals. a 
found useful in laboratory work. 
RECENT BOOKS AND PAMPHLETS. 
Upham, Warren.—Lake Agassiz, a chapter in Glacial Geology. 
Acad. N. S., Vol. 11. From the author. Vol. xt, No. 
Harger, Oscar.—Report on the Isopoda. Bull, Mus. Comp. Anat., YO" o 
Cambridge, 1883. From the author. Tias, hee Inst. 
Dewey, F. P.—Porosity and specific gravity of Coke. Ext. : 5S 
Mining Eng., 1883. 
Hunt, A. E.—Some notes and tests of an open-hearth steel charge - 
plate. Ext. idem, , sde. a 
Stone, G. C.—The determination of Manganese in Spinel. Ext. y Journal, Vo 
Brinton, D. G.—The Folk-lore of Yucatan, Ext. from the Folk-lore , eee 
I, Pt. vitt, London, Eng., 1883. From the author, i: eee 1333. Fro® 
Allen A,.—The Journal of the Postal Microscopical Society, : 
the editor. 
E E I E L E EE oe E E E ara e ly ena E 
Se S 
E EEn LE a E a A ee 
Ext, Bull. Mint. 
made for boilet 
ENEE ES ENAA anin ical E ; : Second | oe 
1 Mineral Analysis. Designed by Professor Geo. G. Grol ES ee. 
Lewisburg, Pa., Science and Health Publishing Co., 1993. 
