NOTES ON CESTODE PARASITES OF SHARKS AND 



SICATES. 



By Edwin Linton, 

 Of the Medical Department of the University of Georgia, Augusta. 



INTRODUCTION. 



Wliile this paper was prepared for publication at the medical 

 department of the University of Georgia, the greater part of the 

 laboratory work upon which it is based was done while I was enjoy- 

 ing the privileges of the laboratories of the United States Bureau 

 of Fisheries, Woods Hole, Massachusetts, and the zoological depart- 

 ment of the University of Missouri. 



All collections made in the Woods Hole region in the months from 

 September to June, inclusive, with the exception of a few dates in 

 the early part of September and the latter part of June, were made 

 by the late Vinal N. Edwards, whose collections were made during 

 a long series of years, and in all the months of the year. Some of 

 1 his material proves to be new ; some of it makes it possible to revise 

 and add to earlier descriptions, which were often regretably meager; 

 much of it supplies new records of habitats, and of seasonal dis- 

 tribution. 



In all cases where the locality from which material was obtained 

 is not given, the Woods Hole region is to be understood. 



Of the many examples of the encysted stages of selachian cestodes 

 on which I have notes I have included but few which have not been 

 satisfactorily identified. The most frequently recurring forms in 

 the Woods Hole region are: Otohothrium crenacolle, Rynchoboth- 

 rium hulbifer, R. imparispine, and Tetrarhynchus tisulcatus. A 

 list of the intermediate hosts in which the larval cestode, Phyllo- 

 hothiiitm loliginis, has been found was recently published (1922?>). 



The valuable Index Catalog of Stiles and Hassall^ makes it un- 

 necessary to burden this paper with extensive references to the lit- 

 erature. I have thought it best, however, to include references to 

 chose of my own papers which deal with the tapeworms of sharks 

 and skates. 



1 Hygienic Laboratory, Bulletin 85. Washington, 1912. 



No. 2511. — Proceedings U. S. National Museum, Vol. 64, Art. 21. 



1 



