Geology and Mineralogy. 409 
exit, is raised ten to twenty fathoms above the sea-level “ at 
such points as seine Merritt’s and. Worth islands.” The 
m to question, as thes have done, the view of Darwin that the 
veri of the Pacific owe their forms largely to the conditions 
ome deer ase 0 ern 
West India coral islands an@ in the Bava gs When the pple 
tion for the atolls has been studied by means of a series of bor- 
ings to a depth of 500 or 1000 pon which shall bring u the rock 
in a core six inches in diameter for examination, science will 
€ positive conclusions as ne 4 e organic source of the reef 
8 
erage may be, ge ology is ape indebted to Professor Alex- 
der Agassiz for his careful and ¢ onvincing oo 
“The writer has been sr on one point. s made to share 
878 ; 
504 ond: a6 pages, BV, ven five large maps and numerous plates 
and wood-cuts.—These two volumes close the series of annual 
Reports of the surve penire on under the asec charge of Dr. 
Hayden and the direction of the Secretary of the Interior—a sur- 
vey that was fruitful in results to science and the country. In 
the letter of transmission of the Report now issued, Dr. den 
Speaks of nee other volumes of the quarto series of reports as re- 
