722 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [4] 



ing and sectioning for anatomo histological study. In final writing all 

 notes were revised and their data incorporated in the description for 

 publication. 



I have not attempted to give complete synonymies, but have in each 

 case given what seem to me to be the more important references. The 

 older synonymy can be found in Diesing's classical work. 



Under the formal heading " habitat," I have given only the host in 

 which I have found the species. For new species this is complete, but 

 it is, of course, incomplete for old species. In the latter cases I have 

 alluded to the usual host or hosts in connection with remarks on the 

 species. 



So far as my investigations go, it would appear that very few of the 

 cestod eutozoa of fish pass their adult stage in different specific hosts. 

 With regard to the encysted forms, however, the range of hosts appears 

 to be greater. 



The nomenclature of fishes used in this paper is that adopted by 

 Prof. G. Brown Goode, in "The Fisheries and Fishery Industries of 

 the United States, Section I, Washington, 1884." I desire to express 

 here my sincere obligations to Mr. Vinal N. Edwards for his valuable 

 assistance in providing material for study. It is but a poor acknowl- 

 edgment of the valuable services rendered by my wife, Margaret B. 

 Linton, in the preparation of this paper, to say that the illustrations 

 which accompany it are the work of her hand. 



Order OESTOIDEA. 



Family I— PSEUDOPHYLLID^E Van Beneden. 

 Dibothriidw Diesiug. 



Dibothrium Rudolphi. 



Usage is about equally divided between the names Dibothrium and 

 Bothriocephalus for this genus. Rudolphi used the name Bothriocepha- 

 lus as a generic title, and divided the genus into two subgenera to 

 which he gave the names Tetrabothrium and Dibothrium. The latter, 

 as used by Rudolphi, had about the same limitations as it now has. 



1. Dibothrium restiforme, sp. nov. 



lEcstis, a cord. J 



[Plate i, Figs. 1-16.] 



I have found it necessary to make a new specific name to accommo- 

 date four Dibothria from the intestine of the rare silver gar (Tylosurus 

 caribbwus). 



The head of the living worm is broad-oval, flat, two-lobed, the lobes 

 longitudinally and somewhat radiately striated, rather squarish or 



