PREPATORY REMARK. 
Tue volume on Zoophytes, to which the following chapters form an introduction, 
includes descriptions of the species collected by the Exploring Expedition, together with 
a comprehensive review of this department of science. All recent zoophytes, excepting 
those of the groups Actinidee, Hydroidea, and Bryozoa, are embraced in the work, with 
full descriptions and references to previous authorities. The whole number of Actinaria 
comprised is four hundred and eighty-three; and of these nearly half are for the first 
time distinguished and described. They are illustrated by an Atlas of sixty-one folio 
plates. 
The volumes form a part of the series published, as the results of the Expedition 
under the command of Cuartes Wiixss, Esq., U.S. N., by authority of Congress. 
James D, Dana. 
New Haven, Conn., 
January 1, 1846 
