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[in Japanese]

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During the course of our research on the Japanese pandalid shrimps, we found a great izumiae OMORI. As mentioned by OMORI (1971), P. izumiae is rather easily distinguished from P. binoculus by having 1) small size, less than 50mm in total length and 8mm in carapace length, 2) no postrostral crest, 3) long dactyli of the last three pereiopods, about half as long as the propodi and 4) "faintly reddish orange" color in the carapace and abdomen. P. binoculus is more than 100 mm in total length and 21 mm in carapace length and bears a prominent postrostral crest and relatively short dactyli of the last three pereiopods. An oval red circle on either side of the third abdominal somite is most remarkable in P. binoculus. Neverthless almost all previous records were done under the name P. binoculus (URITA, 1921; YOKOYA, 1933; MlYAKE, SAKAI & NlSHIKAWA, 1962; FUJINO & MlYAKE, 1970 and ZARENKOV, 1971, etc.) or Plesionika sp. (YASUDA, 1955; KUBO & ASADA, 1957; UTINOMI & HARADA, 1958, etc.). Fortunately we could reexamine a part of the material of them or examine some specimens from the same localities or near the localities, from which the above-mentioned authors collected their P. binoculus or P. sp. We conclude from these examinations that these P. binoculus or P. sp. in literature do not belong to the true P. binoculus but to P. izumiae. P. binoculus is very rare and usually collected solitarily from rather deep water. The present specimens, which are the first record of this species from Japan, were collected from Tosa Bay, Kochi Prefecture. P. izumiae is distributed all over Japan, except for Hokkaido and the Pacific coast of the Tohoku District. In the Pacific coast of southern Japan it is much abundant in depths varying from 40 to 80 m.

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Recent introduction in Japan mainland of two drosophilid species, Drosophila siinulans STURTEVANT and Chymomyza procnemis (WlLLISTON), is reported.

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Morphological and morphometrical studies were performed to elucidate the speciation and racial differentiation of the fish belonging to the genus Leuciscus (=Tribolodon), in addition to the revisional examination of the cephalic lateral-line system as an ideal character for the classification of this group of fish proposed by NAKAMURA (1963, 1969). The materials were collected from various rivers, streams and lakes, ranging from the southern part of Hokkaido to the north of Nagano Prefecture. The present investigation confirmed roughly the results of NAKAMURA (1963, 1969), and the Japanese dace were classified tentatively as follows: Leuciscus brandti (=L. jusanensis, very probably), superspecies, sea-run form. L. hakonensis, sea-run form and freshwater form. L. ezoe, freshwater form. L. taczanowskii ?, sea-run form, found probably in the Pacific side. L. sp. (Nom. Jap.: Ukekuchi-ugui. Uke-kuchi means the feature of the mouth part, showing the protruded lower jaw) freshwater form, found exclusively in the River Agano. It is of interest to know that the individuals with larger number of scales on the lateral line, such as L. jusanensis and L. sp., posses also the larger number of scales before dorsal fin. As stated previously (NAKAMURA, 1963, 1969), by the features of cephalic lateral-line system, the fish were classified into two major groups, such as the A and B types. In the A (L. jusanensis and L. taczanowskii) with larger number of scales on the lateral line, there is found a junction between the postocular commissure (POC) and preoperculomandibular canal (POM), while in the B (L. hakonensis, L. ezoe and L. sp.) no junction is detected between the POM and POC. When the pores of POM were counted, the number in L. hakonensis and L. ezoe is concentrated in 13, while that of the rest three races is in 20. In the case of the pores of supratemporal canal (ST), the number in L. hakonensis and L. ezoe is fewer than that of the rest (more than 9). However, there is a variation of the number of ST in some populations of the sea run form of L. hakonensis, 6 to 8. The secondary sexual characters, such as the features of nuptial coloration and pearl organ, differ among different races. Therefore, it is considered that these characters are intrinsic for each race and useful for classification of mature adult dace. L. sp. (Ukekuchiugui) found exclusively in the Agano River system is a peculiar race in having the mixture of morphometric characters of different races. Further studies including comparative endocrinology are now in progress to clarify the adaptability and evolution of the Japanese dace.

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An island subspecies of the Varied Tit, Par us varius owstoni, feeds on nuts of Castanopsis cuspidata in autumn and winter, and has larger body sizes which seem to be adapted to feed the nuts. The relation between the feeding and the structure in the island subspecies was investigated in comparison with the mainland subspecies P. v. varius. Result obtained was as follows. 1. In body sizes, all eight characters investigated were larger, in the island subspecies than in the mainland subspecies, and the difference was striking in the characters related with feeding such as bill, foot, and body weight (Table 2). 2. The latter point was shown more clearly by the comparison on the proportion of measurements, and it was recognized that the bill and foot of the island subspecies were larger in relation to the wing length which is an index of the body size, and that the island subspecies was also heavier in relation to the body size (Table 3, Fig. 1). 3. In captivity, the efficiency for holding and breaking the nuts in the larger island subspecies was remarkably superior to that in the smaller mainland subspecies (Fig. 2〜Fig. 5). 4. The difference of the feeding efficiency between the two subspecies was clearly resulted from the difference of body sizes. 5. Therefore, it may be regarded that the larger body sizes of the island subspecies are well adapted for feeding the nuts, and the larger body sizes must play an important role in the winter survival of this subspecies.

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In consideration of host-parasite relationship, the distribution of the cave bats, Rhinolophus ferrurnequinum and R. cornutus, was studied in the northern part of Tohoku district. A number of the bats mentioned above were collected in Aomori, Akita and Iwate Prefectures during the years from 1973 to 1975 and the parasitic tapeworms were identified. (1) Hymenolepis rashomonensis was found in R. ferrurnequinum collected from Aomori, Akita and Iwate Prefectures, but Vampirolepis ogaensis was found in R. ferrurnequinum from Aomori and Akita Prefectures. On the contrary, Oligorchis brevihamatus was found only in R. ferrumcquinum from Iwate Prefecture. (2) Except for Akita Prefecture where the author could not collect R. cornutus through the present investigation, H. rashomonensis was found only in R. cornutus from Aomori Prefecture, and V. isensis in the bat from Oname-ana and V. i-watensis in the bat from Matsugasawa-do and Iwai-kutsu. No tapeworm was found in R. cornutus from Momonoki-do and Amabutai-no-ana in Iwate Prefecture. (3) The result obtained from the present investigation revealed that some R. ferrurnequinum in the north of Tohoku district migrate over a wide region and some have a local migration, and the range of migration of R. cornutus is not so wide as that of R. ferrurnequinum, but it is mainly local.

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