The sperm morphology of four shrew species, Sorex shinto and Chimarrogale himalayica (Soricinae), and Crocidura dsinezumi and Suncus murinus (Crocidurinae) belonging to the family Soricidae, was studied with the electron microscope. The Japanese water shrew Chimarrogale himalayica has been regarded as belonging to the subfamily Crocidurinae based on the teeth with white-colored tips. Spermatozoa of the Soricidae were characterized by the presence of a conspicuously long middle piece compared with those of other eutherians as far as we know, its outer dense fibers arranged in a horseshoe fashion and well-developed satellite fibers found in association with the inner aspect of fiber Nos. 5 and 6. However, the C. himalayica spermatozoon differed from other crocidurine spermatozoa in size and shape of the head; namely, the former head took a small spatulate shape, but the latter a large shield-like shape. In addition, the C. himalayica spermatozoon possessed an unusually slender, wavy and electron-dense apical body at the tip of the subacrosomal space surrounded by the smooth inner acrosomal membrane and the proximal centriole had a solid lumen filled with electron-dense materials, both of which are characteristic of the Soricidae. However, other crocidurine spermatozoa were devoid of such a peculiar apical body in the subacrosomal space surrounded by the serrated inner acrosomal membrane and the proximal centriole had a fistulous lumen. The evidence presented here strongly indicates that C. himalayica should be moved from the subfamily Crocidurinae to the subfamily Soricinae.

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We investigated seasonal changes in activity of the northern Ryukyu fruit bat Pteropus dasymallus dasymallus from 1988 to 1990 on the island of Kuchinoerabu-jima and also observed the bats in captivity. In the field, the arrival of the first bat at feeding sites occurred 41 min after sunset on average, and it was earlier in spring and summer than in autumn and winter. Feeding started soon after arrival at the feeding trees. The basic pattern of feeding activity was unimodal, and the principal feeding period was observed within 3-5 hrs of arrival. During the second half of the night, feeding activity decreased, and resting or sleeping was more prolonged than during the first half. In winter, the number of bats visiting feeding sites was reduced, and feeding activity was scarcely observed. The time spent sleeping during the night was closely correlated with the ambient temperature, and the duration of sleeping markedly increased when the ambient temperature fell below 10°C. The bats probably reduce their activity levels and their basal metabolic rates during severe winter conditions.

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As a result of comparison of external, cranial and dental measurements and some qualitative characters of the Hipposideros armiger group consisting of H. a. armiger Hodgson, 1835, H. a. terasensis Kishida, 1924 and H. turpis Bangs, 1901, I came to the conclusion that H. a. terasensis is different from H. armiger at the species level. They seem to belong to different clades. Consequently, I advocate that H. terasensis from Taiwan is not a subspecies of H. armiger, but a distinct species.

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