The antlers of deer have been developed in size and shape through a progressive evolution as forest-dwelling ruminantia. Concerning the function of antlers, many opinions which have a relation to life in the herd at the breeding season have been reported. These discussions, however, referred mainly to the significance of completed antlers other than a few observations on velvety antlers. The present study was conducted to obtain data for a discussion of the physiological function of velvety antlers, in which a consideration that the antler in the process of growth seems to affect the thermoregulatory function of the brain and the body in the summer time is also contained.
1. A two year-old male of the Japanese deer which had growing antlers was used as the experimental animal. The surface temperature of the velvety antler and the body was measured at several positions in specially prepared room of which the temperature was controlled so as to rise from 0°C to 33°C and then fall to 19°C within about 7 hours. The examination was done twice, and similar results were obtained. 2. The temperature of the velvety antlers changed from 5°C to 36.5°C. When the environmental temperature start to rise, the antlers' temperature increased, while when the former started to fall the latter decreased. 3. The temperature responses of the shank and ear against the changes of environmental temperature yielded an S-shaped curve, but the antler temperature increased or decreased in parallel with the environmental temperature. 4. During immersing the velvety antler in stirred ice water, the temperature showed the hunting temperature reaction at intervals of 10-20 minutes with 1-3°C amplitude. 5. For purposes of anatomical and histological observations of the blood supply in the velvety antlers, heads of 2 cases — one is used in this experiment and, another one is also a Japanese deer with velvety antlers, were used. The morphological observation showed that the venous blood returned from the velvety antler by four pathways of which the two veins drained through the cavenous sinus. 6. From these results it is considered that the velvety antlers seem to have a thermoregulatory function. They appear to serve as a thermoregulatory organ to the brain, especially, they act effectively when a sudden change of environmental temperature occurred.
This probable thermoregulatory function of the velvety antlers suggests that it is important for maintenance of the individual during summer time, and it is also suggestive to the evolutionary history of the deer in northern environments in which the daily or seasonal variation in air temperature is very severe.

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Two of the northern most frontiers in the distribution of larger Mogera kobeae that has driven away smaller M. wogura from the original habitat have been found at Agematsu and at Ono, Shiojiri in Nagano Prefecture, Honshu. Change of the boundary-line of the two moles' distributions between 1959 and 1973 was surveyed by means of trapping moles and measuring tunnels. In Agematsu Town, M. kobeae has enlarged the distribution for about 3 kilometers into the range of M. wogura in the 1959-73 period, while at Ono, the two moles have principally showed no change in the distribution in the 14 years. The latter may be due to that Ono is situated at the uppermost area of a branch stream of the Tenryu River, and the habitat (soil texture) is not suitable to the life of larger M. kobeae. M. kobeae has expanded the range to more northern district in the Tenryu River basin than in the Kiso River basin. This may be attributable to that the former basin has much wider habitat for the mole than does the latter, and, hence, the size of the population of the mole is much larger in the former than in the latter. Ecological relationships between the two moles at the abutting area were discussed with the nature of habitat and the morphological characters of moles which might have been produced in relation to the character displacement, the Bergmann's rule, and the general pattern of geographic variation in Japanese moles.

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Lately a good material of the antlers of fossil Megacerotids has been unearthed from the bottom of the Nojiri Lake, Nagano Prefecture, and is preserved in the Geological Institute, Shinshu University, Matsumoto City. The writer, together with Prof. MORI, visited in April, 1973, the lake and the Institute for study, and got the idea of the convincing age of the fossiliferous, as well as culture-bearing, bed there. It yields also the remains of Loxodonta (Palaeoloxodon) namadica naumanni MAKIYAMA and the relics of the Miyagian, as identified by the writer, thus enabling even a worldwide correlation of the strata. In the writers opinion, it belongs to the upper half of the Tokyo Bed and is referred to the Second Section of the Pleistocene, viz, the 2nd Glacial-2nd Interglacial.
Though helplessly misunderstood and confounded by some authors, the upper Pliocene and the Pleistocene Megacerotids in Japan are quite distinct from each other, being even generically so. All the known remains of them of the Pleistocene in Japan would belong to the single species Sinomegaceros mongoliae (BOULE & TEILHARD DE CHARDIN) . The writer could find in the original definition of Sinomegaceroides SHIKAMA no fair reason to make it distinct from Sinomegaceros DIETRICH. The fragmental palmate crown of antler from the flood-plain deposit of the Sagami River, referred to Alces sp. by HASEGAWA, is in the writer's opinion a good material merely of Sinomegaceros mongoliae.
The writer has tried to restore the antlers of the Pleistocene and other Megacerotids in order to make clear how they are distinguished from each other and how they arrange in a fair series of evolutionary succession.

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Kirigamine and Shirakabako plateaus are high plains, made of loam layers and lavas produced by Volcano Kurumayama, and presenting a prairie-like aspect. They are 1200-1925 m above the sea level. Since early, the plateaus have been burned every year by nearly villagers to secure the growth of grass for feeding cattle, and this helped to preserve and develop a grassy plain.
The authors captured small mammals in the grassy plain and in small-scaled virgin forests, secondarily restored forests and afforested larches found in the grassy plain.
The species composition of small mammals markedly varied according to their botanical environment. Clethrionomys andersoni and Apodemus argenteus predominated in the virgin forest, Apodemus speciosus in the sparse forest, and Microtus montebelli in the grassy plain. With step by step destruction of virgin forest into sparse forest and then into grassy plain as the result of burning, the predominance showed a conspicuous shift from Clethrionomys andersoni and Apodemus argenteus to Apodemus speciosus and then to Microtus montebelli.

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