On the Tsu-shima Representative of the Japanese Sable. 161 



XVIII. On the Tsu-shima Representative of the Japanese 

 Sable. By OLDFIELD THOMAS. 



THE late Mr. P. A. Hoist, while collecting birds for Mr. Henry 

 Seebohm in the far East, obtained and sent home five speci- 

 mens of the Marten which inhabits the islands known as 

 Tsu-shima, between Corea and Japan. These specimens are 

 clearly related to the Japanese Sable (Mustela melampus), 

 but differ so much in the details of their coloration as to 

 demand subspecific separation. Two of the specimens are in 

 summer pelage and three in winter, and, for comparison with 

 them, there are in the British Museum one summer and four 

 winter examples of the Japanese form. The summer and 

 one of the winter specimens are co-types of Temminck's 

 species, while the former is, in addition, the type of M.japon- 

 icus of Gray, who, in spite of Temminck's definite account of 

 the seasonal changes, considered the brown summer form as 

 characterizing a different species, and re-named it accordingly. 



Mustela melampus tsuensis, subsp. n. 



Similar to the typical form in size, quality of fur, and in 

 cranial and dental characters, but distinguished by the following 

 colour-characters : 



In winter pelage. General colour above dirty yellowish 

 brown instead of rich orange-yellow. Top of head to nape, 

 instead of only to forehead, ashy greyish white. Muzzle, up 

 to and including the orbital region, and lips (both upper and 

 lower) black ; interramia * brown throat white, in continua- 

 tion with the white of the cheeks and crown, passing on the 

 chest and belly into dark brownish yellow. Fore limbs 

 black from the elbow downwards ; hind limbs black on the 

 feet, brown below the knee. 



In this pelage the most marked distinctions from typicus 

 are the black instead of brown muzzle and lips, the brown 

 instead of white interramia, and white instead of yellowish 

 throat, besides the difference in general tone and greater ex- 

 tension backwards of the ashy colour of the crown. 



* Interramia. The space between the rami of the lower jaw, behind 

 the " chin " but anterior to the " throat." In describing mammals a name 

 is constantly being wanted for this region ; but I have been quite unable 

 to discover whether there is already one in existence, and therefore now 

 suggest one. I have personally felt the want of such a word again and 

 again, especially when describing antelopes, in which the interramia is 

 particularly distinct from either chin or throat. 



