Two distinct groups are recognized among the commensal forms of Rattus rattus as shown in a dendrogram (fig. 2) . The dendrogram was made by the weighted variable group method based on coefficients of differences in the length of hind foot and upper molar series between each combination of broadly accepted commensal subspecies. The first group, i.e. rattus group containing R. r. rattus, brunneus, and diardi, differs from the second group, i. e. tanezumi group containing R. r. rufescens, flavipectus, tistae, and tanezumi, in evidently longer hind foot.
The house rats of Hachijo Is., Seven Islands of Izu, Japan, hitherto recognized as R. r. rattus by the author, are distinguished from tanezumi of Honshu, Japan by much longer hind foot (mean 35.65mm), larger tail ratio (mean 113.7%), and different masseterie plate with obscure antero-upper angle similar to that of R. r. rattus (fig. 3) . Such characters, length of upper molar series, and general coloration of Hachijo specimens well agree with those of diardi, and there are no characters markedly differing from the latter. Therefore the population of Hachijo Is. is identified as R. r. diardi of rattus group. This subspecies is distinguished from R. r. rattus by the coloration of the ventral fur and from brunneus by the slightly but evidently (statistically) smaller tail ratio (table 1) and the lower and thinner masseteric plate.

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Ninety six squirrels are autopsied from March, 1963 to April, 1964 for this study. The volume of stomach contents, measured by the deposition in a messcylinder, seems to be reduced in breeding periods, but this is still uncertain.
Animal material is more often seen in spring and in summer. Most of these are squirrel hairs and ants. In the author's opinion, they may be swallowed with grooming or with the licking of tree-sap. A few Orthopterans are found during spring, and in only one case during spring were some down feathers observed.
Leaves and bark are found in almost half of stomachs throughout the year. Petals occurred in some cases in spring, and fruits and seeds are seen in a total of twenty six cases. No moss and fungus were confirmed. Seven stainings were used for plant substances. JJK reactions show almost every stomach contains starches which may be come from the mast of oaks, Quercus phyllyraecoides. Cork- and lignine-stainings show bark is more often eaten in spring.

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[in Japanese]

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Dr. Pyong Hooi WON of Seoul, Korea, sent me five specimens of Korean bats for identification. After careful examination, these specimens are identified as four species belonging to the genera of Murina, Eptesicus, Myotis, and Pipistrellus, with their new localities in the Korean Peninsula.

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