SOME HYDROIDS OF BEAUFORT, NORTH CAROLINA. 



By C. McLEAN FRASER, Ph. D. 

 University of Iowa. 



INTRODUCTION. 



During the two weeks from August 31 to September 12, 191 1, at the United States 

 Bureau of Fisheries Laboratory at Beaufort, N. C, the facilities for collecting were put 

 at my disposal to such an extent that, although the time was so limited, I was enabled 

 to make a very interesting collection of hydroids. Since very little systematic work 

 has been done on the Beaufort forms, and as the material seemed promising, it was 

 suggested by Prof. H. V. Wilson that a key be made out for the use of others who might 

 wish to study the hydroids of that region. When the material was examined, 51 species 

 were found and seemed to make such work worth while. It is fully recognized that with 

 such a scant survey as the limited time made necessary, this key must be very far from 

 complete, but such as it is it may be useful until somebody has opportunity to make 

 a more careful survey of the whole region. 



In writing this paper an endeavor has been made to have the account of each species 

 as explicit as possible, with illustrations to indicate all special points, so that the casual 

 student of hydroids may be able to make a diagnosis of any specimen of species herein 

 described. For those who wish to go into the matter more deeply, a synonymy reference 

 list has been given, not complete by any means, but including a reference to the original 

 description and to well-known papers or those mentioned in the context. 



To make the paper especially applicable to Beaufort, all the descriptions are made 

 from the Beaufort specimens, except that in some cases others were used in comparison. 

 All trophosome drawings, unless for comparison, were made from Beaufort specimens and 

 all gonosome drawings also, when the gonosome was found. The drawings are all made 

 to the same scale (a magnification of 20 diameters) except where enlarged drawings were 

 needed for detail, in which case this enlargement is indicated in the explanation of the 

 figure. 



Of the 51 species obtained but one is new, though several are new to this part of 

 the coast and four gonosome descriptions are new. Much of the material was in such 

 good condition and contained so many good specimens, that many interesting points 

 were made out. The discussion of these points has been introduced with the regular 

 description of the species, so that the paper, besides being a key, introduces a large 

 amount of new matter which may prove of interest. 



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