Genus Ileptalretus or Bilellostoma. 535 



anterior teeth of each row united at the base; lengtli of head, 

 to first gill-opening, G^ in the total lengtli. 

 Chile. 



1. 380 mm. Valparaiso. * Challenger.' 



2. Ileptalretus stouti. 



Bdellostoma stouti, Lockington, Amor. Xat. 1878, p. 793. 

 Polistotrema stouti, .lord, i^' Evenn. Bull. U.S. iSat. Mas. xlvii. 1896, 



p. ; Everm. &, Goldsborough, Bull. U.S. Fish. Bureau, xxvi. 1900, 



p. 226 (1907). 

 Homm st9uti, Dean, Journ. Coll. Tokyo, xix. 1904, Art. 2, p. 11, 6g. A, 



and p. 20. 



11 to 13 gill-openings; length of head, to first gill- 

 opening, 3^ to 4? iu the total length. 

 Calitornia. 



3. Hejytatretus deant. 



Polistotrema deani, Everm. Sc Goldsborougli, Bull. U.S. Fish Bureau, 

 xxvi. 1906, p. 225, tig. 1 (1907). 



11 or 12 gill-openings ; two rows of 10 or 11 teeth on 

 each side ; length of head, to first gill-opening, 5| to 6| in 

 the total len2;th. 



Alaska. 



4. Hepfatretus decatrema, sp. n. 



Bdellostoma poJytreina (non Girard), Putnam, Proc. Boston Nat. Hist. 

 Soc. xvi. 1873, p. 160. 



10 gill-openings ; two rows of 12 teeth on each side, the 

 3 anterior teeth of each row united at the base ; length of 

 head, to first gill-opening, 4^ to 5 in the total length. 



Chile. 



1-2. 420 & 480 mm. (types of the species). Chile. Dr. Delfiu. 



5. Heptatretus okinoseanus. 



Homea okinoseana, Dean, Journ. Coll. Tokyo, xix. 1904, Art. 2, p. 11, 

 fig. B, p. 20, and pi. i. fig. 1. 



8 gill-openings ; on each side 12 teeth in the outer and 

 10 or 11 in the inner row ; 3 anterior teeth of outer and 2 

 anterior teeth of inner rows united basally ; length of head, 

 to first gill-opening, about 4 in the total length. 



Japan. 



