VJ PREFACE. 



seas ; and this part of the subject has been wrought out with great beauty and minuteness 

 by different investigators since the time of Trernbley and Ellis. But the vast majority 

 of the larger coral zoophytes are in remote regions, and require a patient residence 

 upon the spot to study out their living forms. The voyages of Peron and Lesueur, 

 and Quoy and Gaymard, together with the journey of Ehrenberg to the Red Sea, 

 give nearly all hitherto known with regard to them. It is, therefore, no presumption 

 on the part of the author to say that a large amount of new information was obtained, 

 nor a fact which might not have been anticipated, that such information has detected 

 numerous errors in the received systems or suggested changes of fundamental importance. 

 In making out the Report, it was found impossible, in many genera, to describe the 

 discovered species without giving new and more definite characters to the old ; and the 

 genera themselves sometimes required a modification of their limits, and changes in their 

 associations. In every part of the subject, a thorough revision seemed desirable ; for only , 

 by such a course could the facts obtained be clearly or satisfactorily set forth. The 

 Report, therefore, has necessarily become a Treatise on Zoophytes. Various collections 

 in our country have been consulted in the course of its preparation, among which are 

 Peale's Museum, at Philadelphia ; the Cabinet of the Academy of Natural Sciences, in 

 the same city ; and that of the Natural History Society at Boston: all were liberally 

 thrown open, and every convenience given to aid in the researches. It will appear, from 

 the results, that the plan adopted was the only one that could have done justice to the 

 department of Zoophytes in the Expedition, and honour to the country which had con- 

 tributed so largely in her appropriations to the promotion of science. Out of the four 

 hundred and eighty-three species of zoophytes in the tribe Actinaria, (exclusive of the 

 Actiniae,) which the Report contains, but two hundred and fifty-four, or little more than 

 half, are to be found in previous works. The asterisked names in the catalogues of 

 species, under each genus, show how large a proportion of the whole have been described 

 anew, from specimens examined by the author. 



The Report is indebted to the Journal of Mr. J. P. Couthouy for drawings and descrip- 

 tions of a species of each of the genera, Fungia, Tubularia, and Renilla. Drawings and 

 notes of several of the Hydroidea have been contributed by Dr. C. Pickering. 



The coloured figures of the Actiniae, with two or three exceptions, are from the skilful 

 pencil of Mr. J. Drayton, by whom the descriptions of the species have been drawn up for 

 the volume, from the notes of Mr. J. P. Couthouy, and from his own observations. 



In the preparation of the following pages, Lamarck's Treatise has been a book of con- 

 stant reference, together with the more recent works of Blainville and Ehrenberg. The 

 Memoir by the latter in the Berlin Transactions for 1832, is especially valuable for its 

 original views on the nature and growth of coral zoophytes, and contains, besides, a lar<ro 

 contribution of new species. The labours of Milne Edwards, both through his separate 

 Memoirs, and his Notes and Additions to the last edition of the Anhnnux sans 



