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1. Hemimastodon annectens MATSUMOTO This species, as well as PILGRIM's genotype, is typically bunodont Bunolophodontine, exhibiting no true Serridentine character. There is no reason to remove it to Serridentinus OSBORN, as tried by some authors. 2. Desmostylus cfr. japonicus TOKUNAGA et IWASAKI The tooth-germ with ten columns of Desmostylus found at Yuda, Ninohe District, Prov. of Mutsu, was made the type of the new genus and species, Desmostylella typica by NAGAO, who considered it to be not the third but the second molar. IJIRI's recent study of the germ-tooth, which is in the writer's opinion the third molar, of the type-skull of Desmostylus japonicus shows, on the other hand, that the composition of the tooth in question is different from what observed and expected by NAGAO. The tooth consists of eight columns arranged in four rows. Thus, it has come out more probable that, the tooth-germ from Yuda is actually not the second but the third molar, just as the writer early stated. Judging collectively from the writer's, NAGAO's and IJIRI's observation, the third upper molar of the Desmostylidae might probably have taken the course to evolve from a six-columned stage to many-columned. 3. Stegodon orientalis OWEN Parastegodon akashiensis TAKAI from Akashi, Prov. of Harima, and from Akami-mura, Prov. of Shimotsuke, is, in the writer's opinion, referred not to Parastegodon but to the present species. The writer insists to use the genus Parastegodon not in a too extended sense. 4. Stegodon orientalis shodoensis MATSUMOTO Parastegodon infrequens SHIKAMA from off Akashi, Inland Sea, should be referred to the present subspecies, which is a characteristic of the Middle Pleistocene of Japan. If SHIKAMA maintains its reference to Parastegodon, the writer would ask him to cut his speciment in order to examine how the roots of the molar are. 5. Parelephas protomammonteus (MATSUMOTO), typicus The type-specimen, as well as the specimens as a set, of the present form is by no means that of a sort of indeterminable specimens, representing a full-grown last molar. No need to explain that it, as well as they as a whole, is fundamentally different from the molars of Loxodonia (Palaeoloxodon) in the figure of enamel. SHIKAMA'S statement, as well as DIETRICH's, regarding the determination and nomenclature of the present species and form may not be tenable. 6. Parelephas armeniacus (FALCONER)(Fig. 1) The specimen found by SASA at Nogoro, Chirue District, Karafuto (Saghalin) and reported by him under the name of Elephas primigenius is to be referred, in the writer's opinion, to the present species. 7. Loxodonta (Palaeoloxodon) namadica Naumanni (MAKIYAMA) The specimens from Kuzu Town, Prov. of Shimotsuke reported by TOKUNAGA and TAKAI under the names of Palaeoloxodon namadicus and Palaeoloxodon aomoriensis are, in the writer's opinion, to be referred to the present subspecies, which is a characteristic of the Lower Pleistocene of Japan. The specimens referred by the above named authors to Palaeoloxodon namadicus are the second molars of both jaws, and those referred to Palaeoloxodon aomoriensis the first molars of both jaws. None of them represents, in the writer's opinion, a dwarfed type. 8. Loxodonta (Palaeoloxodon) namadica Yabei MATSUMOTO The type-specimens of Palaeoloxodon aomoriensis TOKUNAGA et TAKAI from Shichinohe Town, Kamikita District, Province of Mutsu, can not be distinguished from the present substpecies, which is a charactristic of the Middle Pleistocene of Japan. They are of a juvenile elephant, in all the likelihood, less than ten years old, the first molars being in use. It is, in the writer's opinion, by no means a dwarfed type. 9. Cervus (Axis) praenipponicus SHIKAMA Capreolus (Capreolina) mayai TOKUNAGA et TAKAI can not be referred to Capreolus, as the antlers of the named authors' species are too large to be so. We have a lot of examples of deformed antlers chiefly under a highly aged condition of Japanese sikas. Judging from
社団法人日本動物学会の論文
1938-12-15

本邦産化石哺乳類に就て

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