PRELIMINARY NOTE ON THE SALMON AND TROUT OF JAPAN. II9 



gorbshd) of North America. For my part, I am rather inclined to think 

 that it is very similar to One. perry i HlLG. (=Onc. yessoensis HlLG.) and 

 also to Salmo macrostoma GÜNTHER ; for the general shape and propor- 

 tions, the form of caudal fin, the dentition, etc. combine to justify that 

 assumption. I may here describe some of the important characters 

 of Salmo mason Brevoort for the purpose of clearing- up the confusion 

 relating to this species. 



Salmo masou Brevoort : D. 14-16, A. 14-18, scales 25-32/130- 

 140/29-35, Coec. pyr. 40-55. Depth 3 -| and head 4 \ in total length 

 (without caudal). Eye 10 in head and 2 \ in snout. Maxillary reaches 

 beyond the posterior margin of eye. Teeth smaller than those of 

 the "shake" [One. keta) ; in one series, on both jaws and palate ; a few 

 or none on vomer. Caudal lunate or straight behind in the adult. 

 Dorsal, caudal and the back with a few dark brown spots. The tip of 

 the dorsal is sometimes colored black. This species is found from Kishiu 

 northward, but is most abundant in the northern Hondo and in the Hok- 

 kaido. From winter to early spring it approaches the shore to ascend 

 rivers as far as or beyond the rapids and falls, at any rate to a point 

 which is never reached by the " shake." The figure in Brevoort's 

 note is likely from the spring-run, and the specimen that HILGENDORF 

 named One. yessoensis is piobably a winter catch. The sea-run 

 individual attains a length of about 60 cm., while the land-locked, called 

 " ame no uwo " in southern Japan, is usually smaller. GüNTHEr's 

 Salmo macrostoma is nothing else than the '' ame no uwo." The parr, 

 called " yamabe " or "amago," remains for two or three years in the 

 upper streams where it grows to about 20 cm. in length. Brevoort's 

 " Salmo-young ?" is precisely the parr of this species as was suggested 

 by GÜNTHER. 



Hilgendorf's One. hctberi seems to be identical with One, keta 

 Walb., as Jordan and SNYDER have pointed out. This is the most 

 abundant salmon in Japan, the annual catch of the fish amounting to 

 about 7.000. OOO kg. The scales in One. masou of JORDAN and 

 SNYDER are of nearly the same size as those of the American hump- 



