OCR Text |
Show 1905.] MAMMALS FROM JAPAN. 349 3 . 373, 374. $ . 375, 376. Kuma, Ehime Ken, Shikoku. 1200'. 3 . 459, 460, 461. $ . 452. Kawachi, Miyasaki Ken, Kiu-shiu. 1500'. 3 . 390, 391, 402, 411, 412, 425, 436, 437. ? . 393, 418, 419 426, 433. Takamori, Kumamoto Ken, Kiushiu. 1850'. 3 . 483, 498, 499. $ . 484, 491. Tano, Miyasaki Ken, Kiushiu. 500'. " Common everywhere." Even with this fine series, combined with that sent by Mr. Gordon Smith, I am unable to trace completely the relation of the presence of spines in the fur to season and sex. Many specimens of each sex are spinous, many spineless, and in a general way it is clear that spines are a character of summer, while they are rarely or never present in the winter pelage. Two examples, however, killed in the middle of December have spines, and one from Shikoku, killed in February, so that there are evidently exceptions to the general rule. Young specimens, before the development of the rufous colour, are always spineless. The mammary formula in this species is 2-2 = 8. It appears probable that Temminck's Mus argenteus, also described in the ‘ Fauna Japonica,' was based on small spineless specimens of M. speciosus. The following are the dimensions (in mm.) of a pair from the Izu peninsula :- 3 . Head and body 128 ; tail 112 ; hind foot 24 ; ear 16. „ „ 115; „ 105; „ 24; „ 15. 3 0 . M icromys speciosus a in u , subsp. n . 3 - 10. Jozankei, near Sapporo, Hokkaido. $ . 26. Shinshinotsu, near Sapporo, Hokkaido. j . 108, 117. Aoyama, Hokkaido. As in true speciosus, but with rather longer feet and longer skull. General characters as in the M. speciosus of Hondo, with the same dark fulvous colour blackened along the dorsal area and the same whitish underside. Fur similarly either spinous or spineless. Hands and feet greyish white. Feet longer and heavier than in true speciosus. Skull rather narrower and more elongate than in true speciosus; palatal foramina longer. Dimensions of the type, measured in the fiesli:- Head and body 118 mm.; tail 107 ; hind foot 27'5 ; ear 15. Skull-greatest length 31; basilar length 25; nasals 12• 2 ; interorbital breadth 4-8; breadth of brain-case 12-8; palatilar length 14-4; diastema 9'5 ; palatal foramina 518 ; length of upper molar series 4-2. Hab. Hokkaido. Type from Aoyama. |