Of four species referred to in this note, Mysella paula (A. ADAMS) has been reported from the fossil beds of Tako-mati, Tibaken by Messrs. SUZUKI and TAKAI, while Nassarius gemmulatus (LAMARCK) from Okine, Nagai-mati, Kanagawa-ken is listed by Mr. SUZUKI in his paper “On the Pliocene series near Atuki, Kanagawa Prefecture. Part II” (Jour. Geol. Soc. Tokyo, 39, 462, 1932). I discovered other localities of these species where two other species were found, namely, Mactra dolabrata REEVE and Searlesia simosensis n. sp. These specimens are stored in the Tokugawa Institute of Biological Research.

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A name Desmostylus mirabilis nov. is proposed for the remain recently acquired from a tributary of the Keton-gawa in Japanese Saghalin, which, the writer thinks, represents a species distinct from D. hesperus MARSH and D. japonicus TOKIJNAGA and IWASAKI, the two well established species of the genus. It has a much larger skull with a narrower parietal region and a smaller internoanterior column ofthe last upper premolar than the Oregon form and differs from D. japonicus in being provided with a broader M² and a smaller P⁴ in the upper jaw and a broader M² in the lower. The columns of the lower M₂ are in the new species 7 in number instead of being 6 and those of the upper M₃ seem to be less slender.

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