60 BULLETIN 69, UNITED STATES NATIONAL MUSEUM. 



Generic diagnosis. — Tetrabothriidse : With the characters of the 

 family. 



Type-S'pecies. — B othriocephalus macrocefhalus K-udolphi, 1810. 



TETRABOTHRIUS ARCTICUS Linstow, 1901. 



For description see Linstow, 1901e, pp. 285-286, fig. 42. 

 Host. — Somateria moUissima. 



TETRABOTHRIUS CYLINDRACEUS (Rudolphi, 1819) Diesing, 1850. 



For description see Fuhrmann, lS99b, pp. 872-873 (Prosthecocotyle 

 cyUndracea) . 



Hosts. — Rissa tridactyla., Larus Ixyperhoreus., Larus marinvs, Larus 

 argentatus., Larus canus, Larus atricilla, Xema sahini, Sterna 

 maxima, Uria troile. 



TETRABOTHRIUS DIOMEDE^E (Fuhrmann, 1900). 



For description see Shipley, 1900c, pp. 557-558, pi. 56, figs. 27-29 {Prosthe- 

 cocotyle diomedece). 



Host. — Diomedea exulans. 



TETRABOTHRIUS EROSTRIS (Lonnberg, 1889). 



For description see Fuhrmann, lS99b, pp. 871-872 {Prosthecocotyle 

 erostris). 



Hosts. — Rissa tridactyla, Larus onarinus, Larus argentatus, Lams 

 canvs, Sterna hintndo. Sterna ijaradiscea. 



TETRABOTHRIUS HETEROCLITUS Diesing, 1850. 



For description see Fuhrmann, 1899b, p. 874 {Prosthecocotyle heterocUta) ; 

 1899c, pp. 648-650, figs. 4-8 {Prosthecocotyle heterocUta). 



Hosts. — Pufinus puffinus., Puifinus kuhli, Priocella glacialoides., 

 Daption cafensis., Diomedea exidans, Dioinedea albatrus. 



TETRABOTHRIUS MACROCEFHALUS Rudolphi, 1819. 



For description see Fuhrmann, lS99b, pp. 873-874 {Prosthecocotyle 

 macrocephala ) . 

 Hosts. — Gavia stellata., Gavia arctica, Gavia irnmer, Colyinhus 

 auritus. 



TETRABOTHRIUS MONTICELLII (Fuhrmann, 1899). 



For description see Fuhrmann, 1899b, p. 870 {Prosthecocotyle monticellii) . 

 Host. — Fulmarus glacialis. 



TETRABOTHRIUS PELECANI Fuhrmann, 1908. 



For description see Fuhrmann, 1899b, pp. 875-876 {Prosthecocotyle pelecani 

 aquilce). 

 Hosts. — Sida leitcogastra, fFregata aquila. 



TETRABOTHRIUS PORRIGENS Molin, 1858. 



For description see Molin, 1861c, p. 237, pi. 5, figs. 18, 19 {Tetrabothrium 

 {Orygmathol)othrium) porrigens). 



Host. — Nycticorax nycticorax. 



TETRABOTHRIUS TORULOSUS Linstow, 1888. 



For description see Fuhrmann, 1899c, pp. 643-648, figs. 1-3 {Prosthecoco- 

 tyle torulosa). 



Host. — Diomedea albatrus. 



