UNITED STATES 



EXPLORING EXPEDITION. 



DURING THE YEARS 



38, 1839, 1840, 1841, 1842. 



UNDER THE COMMAND OF 



CHARLES WILKES, U. S. N. 



ZOOPHYTES. 



BY 



JAMES D. DANA, A. M., 



GEOLOGIST OF THE EXPEDITION, 



MEMBER. OF THE AMERICAN ACADEMY OF ARTS AND SCIENCES OF BOSTON, 

 ACADEMY OF NATURAL SCIENCES OF PHILADELPHIA, ETC. 



WITH A FOLIO ATLAS OF SIXTY-ONE PLATES. 



PHILADELPHIA: 

 LEA AND BLANCHARD. 



1848. 



