The present paper describes abnormal characters found in some inbred strains of white rats and mice occurring in our laboratory. The abnormal characters found in white rats are; 'tailless' or 'vestigial tail', 'incisor-overgrowth', and 'screw neck'. These found in mice as follows; 'screw neck', 'waltzing', 'crooked tail', 'hairless', 'imperforate vagina' and 'spontaneous tumer'. At present we cannot say whether these abnormal characters are heritable or not, since the genetical tests have been now going on.
During the Meiji Era, endemic birds and animals decreased also on the Bonin Islands. Bonin Flying Fox Pteropus pselaphon Lay decreased extremely, and as to the birds, Bonin Islands Grosbeak Chaunoproctus ferreorostris (Vigors), Kittlitz's Ground-thrush Aegithocichla terrestris (Kittlitz), Bonin Night-heron Nycticorax caledonicus crassirostris Vigors, Bonin Wood Pigeon Janthoenas versicolor (Kittlitz), etc. died out. The increase of inhabitants and the deforestation of virgin forests seems to have put pressure upon the permanent residents. however, it is noteworthy that so many birds have been the victims. Those of Megapode Megapodius also seemed to have been in existence before the Meiji Era. In the 25th year of Meiji (in 1892) the Game Law was issued for the first time and the birds not to be hunted, that is, the protected birds were legislated. Later, instead of legislating the protected birds, those to be hunted were limited so that the birds and mammals to be protected became much increased in kinds. While planning to breed the birds to be hunted artificially, we ordered those of foreign breed from other countries when necessary, and tried to breed them. Korean Ring-necked Pheasant Phasianus colchicus karpowi Buturlin were let off in Hokkaido in the end of 1930 and have spread out all over favourably since then. Chinese Bamboo Pheasant Bambusicola thoracica thoracica (Temminck) which had been originally produced in China and let off in Tokyo in 1919 became a typical naturalized family in Japan and is being named as a bird to be hunted. The Game Law was revised after the War, and they came to lay stress upon the protection of birds and animals. The bird week was established and the protective movement of the wild life is very active, as far as the movement is concerned. With the view of utilizing them it became active year by year after the Meiji Era to remove an animal family from one place to another and naturalize them. Oncorhynchus nerka (Walbaum), Plecoglossus altivelis Temminck et Schlegel, Hypomesus olidus (Pallas), etc. are all of removed instances. Bull Frog Rana catesbeiana Shaw and Toad Bufo marinus Linné were removed from foreign countries to Japan. Although the former was introduced from the States, its frozen meat is exported to the States vise versa. The latter was introduced into Formosa from Hawaii in 1935, and did much in controlling the scarabaeid beetles harmful to sugar cane. To import the natural enemy for exterminating injurious animals has been practised since the Meiji Era. Common Indian Mungoose Mungos mungo (Gmelin) which had been brought from India in 1910 were let off in the Okinawa Mainland of Ryukyu and Tonaki Island, and did no small service in exterminating Trimeresurus flavoviridis (Hallowell). More than 40 years have passed since then, and yet there are still a small number of their posterity there. Many instances that unexpected transference and importation of birds and animals threw Japanese Fauna into disorder have been found, and quite many of such invaders have appeared since the Meiji Era. Into Bonin Islands, Japanese Pit Viper Ancistrodon halys blomhoffi (Boie), Spotted Scorpion Isometrus europaeus (Linné) came after the year of Shôwa began. The disagreeable Tick, Bdellonyssus bacoti (Hirst) was introduced to Japan after the great earthquake in 1923. Slug Limax flavus Linné had already come to Japan in the middle of the Meiji Era. Swamp Crayfish Cambarus clarkii Girard came into Japan in 1930 for the first time, and now they are in existence almost all over the country except Aomori pref., Iwate pref., Oita pref., Nagasaki pref., Miyazaki pref. and Kagoshima pref. not invaded. However, they are considered to spread out all over the Kyushu area some day.
The Gem-faced Civet, Paguma larvata, belonging to the Viverridae occurs in southwestern China, Formosa, Indo, Malay, Borneo and Burma. It is divided into eleven subspecies. It has been captured in Yamanashi Prefecture frequently since a few years ago and once in Shizuoka Pref. In the villages of Kunado, Tomisato, Furuseki and Okochi, Nishiyatsushiro-gun, Yamanashi Pref. (see Fig. I), one or two individuals of them have been obtained in every hunting season. The writer got one male which had been captured at Furuseki Village on February 21, 1954. Its measurements are given in Table 1. Some chestnuts and four seeds of the wild pear were found in its stomach. A pair of the animals was captured in the suburbs of Shizuoka City in Shizuoka Pref, . in December of 1950. In fact, not a few of them are likely to occur in this area, because most hunters know the habits and habitats of this animal. It seems that this animal was imported some fifty years ago, and has become naturalized in Japan.
1. Roost-dead Grey Starlings, Sturnus cineraceus, were collected through the winter roosting period at three large roosts, Koshigaya in Saitama, Shinhama in Chiba and Kozukue in Kanagawa Prefectures. 2. The roosts were used from November to middle March. The dead birds were found from January at Koshigaya and from Feburary at Shinhama and Kozukue. 3. Research areas for collection of roost-dead birds were marked, which were 33m2. (total of 3 sections), 116m2. (total of 3 sections) and 466m2. (total of 4 sections) at Koshigaya, Shinhama and Kozukue respectively. But, actual research area for dead-bird collection was much larger at Koshigaya, and these research areas covered 50%, 30% and 90% of entire roosting areas at Koshigaya, Shinhama and Kozukue respectively. In all, the numbers of dead birds collected were 40 at Koshigaya, 10 at Shinhama and 24 at Kozukue, and except only 5 examples, the cause of death was a same kind of disease. Two Dusky Thrushes and one Brown-eared Bulbul, probably of this cause, were found dead. 4. The total number of roosting birds were determined by counts of returning birds to the roost which was: 50, 000 birds at Koshigaya, 8, 000 birds at Shinhama and 6, 000 birds (probably underestimated owing to a windy day count) at Kozukue. 5. The pathological diagnostic symptoms characteristic to the roost-dead birds were: 1) Cranial hemorrhage of various degrees occurring in the brain and skull (between the bony plate) which often accompanied severe orbital hemorrhage and protrusion of eye-balls caused by 'flooding' of the brain into the orbit. 2) Congestion of various degrees in the lung, which is usually heavier on the right side. 3) Often pathologic enlargement of the heart filled with venous blood. 4) Often hemorrhage of jugular vein or along the spinal cord (after Prof. Miyamoto) and the capillaries of various body parts. The gizzard was always, except a single case, empty. The pectoral muscles were normal or slightly, or rarely considerably, weakened, and the fat varied in amount by individual from much to none. 6. Young Sparganum mansoni (Cestoda) were found in 8 birds out of 69 examples examined, parasitizing subcutaneously on the surface of pectoral muscles or inner side of the thigh muscles; probably the first record in wild birds. It was also found in the intestine in 26% examples examined, and other parasite, Acanthocephala (and one Cestoda sp.) was found in 21% examples. Pathological examination made by Prof. Tabe, as well as Dr. Kametani and Miss Kihara, parasitologists, did not prove the presence of cercaria and eggs of Gigantobilhazia sturniae Tabe (1948) known in this starling from other prefectures. Results of anatomical, histological and some bacteriologic and pesticide examinations done by Prof. Miyamoto are also included, but direct factor causing the fatal cranial and lung diseases has not been clarified. 7. Ecologically, it was found that 1) Average 71%, even 80% at Koshigaya, of the roost-dead birds were males, 3) Seasonally, January and February were the peak of the disease. Considerations were given from some ecological point of view. 8. The roost-mortality was estimated from two calculations. The roosting density was estimated conservatively as 15 birds in 1m2. (indirect photographic data, though night flash-photos were not available were considered), and based on the collected dead birds within the measured research areas, the mortality was estimated as 1.01% at Koshigaya, 0.46% at Shinhama and 0.24% at Kozukue. The high % of Koshigaya was apparently due to too small measured area. On the other hand, the mortality was calculated also the other way based on the % of estimated total of dead birds, calculated from the collected dead birds and the % of area covered to entire roost area.