Partial sequences for the mitochondrial cytochrome b gene (367 bases) and 12S ribosomal RNA (rRNA) gene (301 bases) of the Japanese sika deer Cervus nippon from three localities (Shiretoko in Hokkaido, Mt. Goyo in Iwate Prefecture, and Tsushima Island in Nagasaki Prefecture) were determined by using direct sequencing of single-stranded DNAs amplified by polymerase chain reaction. Molecular phylogenetic trees, based on nucleotide sequences of both genes, showed that the sika deer was clearly separated from the pronghorn and the cow. Among the sika deer sampled, individuals from Shiretoko and Mt. Goyo shared identical sequences for each gene, indicating the close relationship between these two sika deer. Our results also indicated that the sika deer on Tsushima Island are distantly related to those of Shiretoko and Mt. Goyo. This is the first report of the mitochondrial DNA sequences of the sika deer.

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In order to reexamine the taxonomic position of Anderson's redbacked vole from the Kii Peninsula, Japan, molars from 20 old specimens were examined to see whether their roots were closed or not. In addition, molar occlusal enamel patterns, and craniometric data, based on 160 specimens ranging in age from birth to day 1,116, were compared with those of Anderson's red-backed voles from Mt. Yatsugatake and wild-caught specimens of Clethrionomys rufocanus bedfordiae. All normal specimens from both the Kii Peninsula and Mt. Yatsugatake had molars with open roots, though one aberrant specimen from each population exhibited signs of root-closure. Almost no differences in molar occlusal enamel patterns were noticed between the Kii Peninsula and Mt. Yatsugatake populations. An analysis of the parietal width demonstrated that the Kii Peninsula and Mt. Yatsugatake populations belong to a cline. The cranial growth pattern of the Kii Peninsula population resembled more closely that of Eothenomys smithii (Ando et al. 1989) than that of C. r. bedfordiae. Taking the above facts into consideration, it is concluded that Anderson's red-backed voles inhabiting the Kii Peninsula have a close taxonomic relationship with voles from Mt. Yatsugatalte. Furthermore, the author, supporting the opinion of Aimi (1980), considers the voles of both populations to belong to one species, Eothenomys andersoni.

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Postnatal growth and development of captive Anderson's red-backed voles (Eothenomys andersoni*) from the Kii Peninsula were investigated from birth to day 150. The body weight of both sexes increased rapidly until day 40, growth rate then slowed, and finally ceased by day 50. In males, however, a secondary increase in body weight occurred from day 70 until day 150. The head and body, and tail lengths of both sexes increased rapidly until day 30. Thereafter, the head and body length of females from day 60, and the tail length of both sexes from day 40, continued but slowly. Head and body length of males showed a secondary increase, though loose. Significant differences in body weight between males and females were recognized from day 30 to day 50, and again from day 90 ; in head and body length from day 30 ; in tail length from day 40, and in hind foot length from day 40, but not in ear length. The lower incisors erupted on day 3.6, the upper incisors on day 4.9, the dorsum of young was fully covered with hairs by day 7, the fore digits separated on day 7.9, the hind digits on day 9.1, the juvenile pelage was completed by day 12, the eyes opened on day 12.7, and weaning occurred on day 14. The growth and developmental patterns of voles from the Kii Peninsula were found to generally resemble those of Eothenomys smithii, essentially an intermediate form between Microtus and Clethrionomys.

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In order to reexamine the taxonomic position of Anderson's red-backed voles in question from the Kii Peninsula, the reproductive compatibility among local vole populations from the Kii Peninsula, Nagano and Fukushima was examined by crossbreeding experiments. Fertility of hybrids was ascertained until F4 in five cross types between Kii Peninsula female and Nagano male voles and to F3 in four cross types of Nagano females with Kii Peninsula males. The resulting F5 and F4 hybrids matured normally (in Line I). Moreover, F1 hybrids resulting from one cross type involving a Kii Peninsula female and a Fukushima male, and in one cross type involving a Fukushima female and a Kii Peninsula males, also, showed healthy growth (in Line II). Thus, the reproductive compatibility between both populations (in Lines I and II) was confirmed. Such reproductive compatibility among these three local populations of the Anderson's red-backed vole strongly supports the belief that all belong to one species, Eothenomys andersoni.

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In order to resolve taxonomic problems among the Japanese moles, Mogera spp., I compared the five main diagnostic skull characters among all the known taxa in the genus using, as a basis, the previous work by Abe (1967). A total of 612 specimens were examined, including the type specimens of M. wogura, M. w. kobeae, and M. w. kanai of Japan, those of M. w. coreana of Korea, M. hainana of Hainan and M. latouchei of south-east China, and others from the Far East maritime region of Siberia and Taiwan R.O.C. It was concluded that the mole ranging across the southern half of Japan, previously known as M. kobeae, is in fact a synonym of M. wogura and should be referred to as such. The mole previously called M. wogura with its main range to the northern half of Honshu is henceforth called M. minor. Four species of the genus Mogera: M. wogura, M. minor, M. tokudae, and M. insularis, are thus recognized as occurring in east Asia.

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The diets and abundances of three sympatric shrew species (Sorex unguiculatus, S. gracillimus, and S. caecutiens), food resource conditions, and environmental characteristics were investigated in three habitat types (riparian forest, wind-shelter belt, and spruce forest), during seasons without snow-cover in northern Hokkaido, Japan. S. unguiculatus outnumbered S. gracillimus in both the riparian forest and wind-shelter belt, and vice versa in the spruce forest. S. caecutiens was rare in the study area. Abundances of S. unguiculatus and S. gracillimus seemed to be unrelated to those of their principal foods. The main prey of S. unguiculatus was earthworms, whereas S. gracillimus and S. caecutiens mainly consumed small terrestrial arthropods. S. unguiculatus tended to consume more earthworms in the spruce forest than in the other habitat types. The earthworm consumption appeared to directly reflect their availability per capita. Food consumption by S. gracillimus tended to be constant regardless of the habitat type.

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