[in Japanese]

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1. One of the large sesarmoid crabs, Neoepisesarma(.Neoepisesartn-a)lafondi (JACQUINOT & LUCAS) has been obtained for the first time from Iriomote Island, Okinawa. The full-grown male of this species has a tympanum on each fourth thoracic sternum. The movable Anger of male cheliped is marked with about 120 tubercles on the lontitudinal ridge of its upper border. 2. Uca dubia STIMPSON and U. dussumieri H. MlLNE EDWARDS are closely related with each other. In U. dubia, however, the outer surface of the palm of male larger cheliped is uniformly bright red; in U. dussumieri, the same surface is longitudinally striped with deep brownish red near the median portion, but the upper surface is bluish white. The anterior pleopod of male of U. dubia is provided with a long tube-like apical process; in U. dussumieri , it is distally obtuse and the apical process is very short. 3. Charybdis granulata DE HAAN has long been regarded as a synonym of Ch. natator (HEKBST), but it is valid. In Ch. granulata, the lower border of palm is only irregularly squamose, not sulcate, while in Ch. natator, the same border is squamose and longitudinally sulcate. The penultimate segment of male abdomen of Ch. granulata is rather rounded on lateral borders, that of Ch. natator, the outer borders are rather straight and convergent. 4. Kraussia integra DE HAAN (Fam. Atelecyclidae) can be divided into two species. The one, typical integra has the frontal margin quadrilobate, while the other ( = K. truncatiforns SAKAI, 1974--Researches on Crustacea, No. 6, p. 90) has the same margin subtruncate and bilobate.

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Melanic forms of the ranunculus leaf-miner, Phytomyza ranunculi (SCHRANK), exhibit the overwintering generation and the non-melanic ones indicate the following generations. Flies reared at low temperatures develop melanic pigmentation on the entire mesonotum whereas those reared at high temperatures are usually trivittate on the yellow ground colour of the mesonotum. The degree of melanization is determined by low temperature experienced during the pupal period. The host-plant and larval density do not affect the development of melanization, and the photoperiod is also not an influential factor on the pigmentation of the mesonotum.

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A key to the Japanese species of the genus Dynatosoma is given, and three species: I). cainurum, longicorne and spinimanurn, are described as new. Mycetophila maculipes MATSUMURA is synonymized with D. igromaculaturn LUNDSTROM. The genus Dynatosoma is widespread, with the largest number of species in the Palaearctic region. Three Japanese species, D. maculipes (MATSUMURA), D. major f. sapporoensis OKADA and reciprocurn WALKER, have been recorded, but maculipes is treated here as synonym of nigromaculaturn LUNDSTROM. Three new species and one newly recorded species are described herein. We wish to thank Dr. S. TAKAGI of the Entomological Institute, Hokkaido University for the loan of specimens.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Morphology of the so-called retractor muscle was studied in 7 species of sea-stars, and the followings were observed. 1) This structure shows various forms in different species. 2) The "retractor muscle" consists of connective tissue and muscle strands, the former being quantitatively the main constituent. It was concluded that the "retractor muscle" is not muscle literally and the function may not be restricted only to retractor.

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In order to elucidate the faunal characteristics of a brackish lake, Kamo-ko, located in Sado Island in the Japan Sea, a biological survey was carried out during these several years. This lake, 4.86km2 in area, 17.2km in circumference, and 8.7m in the greatest depth, is famous and active for oyster cultivation, and its mouth communicates with Port Ryotsu, i. e., Ryotsu Bay, by a narrow channel, 200m long and 28m wide. Physico-chemical analyses and limnological observations including paleo-liinnological investigations using 18 m core-sample of the bottom were undertaken to know the environmental conditions of the lake. In all ca. 160 species of animals including ca. 50 species of teleost fishes collected up to the present were listed in this paper. All animals, except one leptostracan Crustacea (Nebalia bipes), were of common occurrence in the coasts of Sado Island, however. It is the first characteristic of the faunal elements of Lake Kamo-ko that the tunicates (Ciona intestinalis, Ascidia zara and Botrylloides violaccus), sponge (Ilaliclona permollis) and bivalve mollusk (Mytilus edulis) are dominant species attached to the bamboo-made rafts and the strings suspended from the rafts for oyster cultivation. The bryozoans (JB-ugula neritina and Caulibugula clliata) are also abundant in this lake. The bottom consisting of sand and sandy mud is very narrow and is confined to the marginal zone of the lake. The eel grass (Zostera marina and Z. nana) and other rooted plants flourish in this zone. Most of the bottom covered deeply with a sedimentation of the black mud is devoid of oxygen, seaweeds and benthic fishes. But, even in this worse environment, there are found some polychaetous annelids (Lumbrincris brevicirra, Cirriformia tentaculata and Capitella capitatci) and bivalve mollusk (Musculus senhousia and Modiolus agripetus) which are able to tolerate water pollution. The paucity of organism on the bottom is the second characteristic of the fauna of this lake. The third point is exhibited by the rapid propagation of the recently immigrated barnacles (Balanus eburneus and B. improvisus) insted of other foreign barnacles (73. amphitrite and B. albicostatus). To obtain much more information, further investigations are now in going progress.

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It has been known that two different species of hynobiid salamanders occur in Yamanashi Prefecture, central Honshu, Japan. They are Onychodactylus japonicus and Hynobius naevius kimurae. However, detailed distribution of them within the prefecture has not been clarified yet. The authors have investigated the ecological distribution of the two species in Yamanashi Prefecture. The results obtained show that O. japonicus commonly lives in the upper parts of streams everywhere in the surveyed area, but that H. n. kimurae occurs only in limited areas of Kitakoma, Minamikoma and Kitatsuru. Vertically, the former species generally inhabits mountains between 600 m and 1,700 m in altitude, while the latter is found between 200m and 950m above sea-level.

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