日本産食肉類4種の乳頭式について

抄録

Although the mammal formula seems to be considerably important for classification in many groups of mammals, there are only a few published records of them among Japanese carnivorous species. Therefore, the following data, obtained by the author during recent few years, may contribute to this field.
Selenarctos thibetanus japonicus (SCHLEGEL, 1857) —2+1+0=6 _??_juv.
Vulpes vulpes japonica GRAY, 1868—2+1+1=8 _??_ ad.; 2+ (1-2) +1=9 _??_ ad., with an additional nipple at the left side of abdomen.
Nyctereutes procyonoides viverrinus TEMMINCK, 1844—1+2+1 =8 1 _??_ & 1 _??_juvs.; 0+2+2=8 _??_juv.
Meles ineles anakuma TEMMINCK, 1844—1+1+1=6 _??_ ad.