A single adult specimen (205.1 mm standard length) of Lined Butterflyfish, Chaetodon lineolatus Cuvier, 1831, collected in 1932 from Onahama, Fukushima Prefecture, northern Japan, was discovered in the fish collection of the Department of Zoology, the University Museum, the University of Tokyo. The previous northernmost Japanese record of the species being the Boso Peninsula, Chiba Prefecture, most records from southern Japan have been of juveniles. Accordingly, the present specimen represents the first record of the species from the cold-water area off northern Japan (northernmost record of the species), and indicates that at least limited dispersal of tropical fishes to northern Japan occurred in the 1930’s, when water temperatures were estimated to have been almost 2˚C lower than in recent years.

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Intra-and interspecific chasings of immature butterfly fishes were studied in an exhibition tank (110cm×170cm×80cm) of the Suma Aquarium. Observations were made on 35 fishes belonging to 13 species in October 1961. For seven species, Chaetodon collaris, C. auriga, C. lunula, C. lineolatus, C. vagabundus, C. melanotus and Heniochus acuminatus, among which nine species had more than two individuals each in the tank, intraspecific chasing was far more frequent and eminent than the interspecific one. On the contrary, though only few data were available, the other two species, Chaetodon nippon and C. ephippium, appeared to chase fishes of other species as well as those of their own species. For the remaining species, it is at present difficult to conclude with certainty. Interspecific chasing of Heniochus acuminatus is concentrated mainly to H. singularius, and the latter chased the former back, but hindered no other species. This may suggest that fish is likely to chase a fish of another species of shape and colour resembling its own. The frequency of intraspecific chasing in any species was much higher before and during feeding than after, while the frequency of interspecific chasing decreased apparently before and during feeding.

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Histological observations on gonadal formation and hermaphroditism in 16 species (4 genera) of Japanese butterflyfishes (Chaetodontidae), included a detailed study of the former in Chaetodon auripes from central Japan. In this species, the gonads of 24 young specimens (<36.4 mm SL) were sexually undeter mined, whereas those of 16 larger specimens (39.4 mm SL to 55.5 mm SL) had begun initial differentiation into an ovary, having formed an early parovarian type ovarian cavity. Sex changes occurred in immature ovaries, which initially became intersexual gonads with many seminal lobules forming in the ovigerous lamellae and eventually matured into secondary testes (each concurrently retaining an ovar ian cavity). No specimens were found with gonads that had developed directly into a testis from a sexually undifferentiated stage. In Forcipiger flavissimus, three stages of gonadal sex succession, viz., ovaries with a parovarian type ovarian cav ity, intersexual gonads and secondary testes with a rudimentary ovarian cavity, were found. In Hemitaurichthys polylepis and Heniochus diphreutes, intersexual gonads of both ovarian-and testicular-types were found. Accordingly, the occur rence of normal, although non-functional, hermaphroditism and sex change from female to male is now established in all of the Japanese chaetodontid species stud ied.

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1. The writer collected egg-batches of the cabbage moth, Mamestra brassicae from eight lacalities distributed from the northern to the south-western part of Japan, viz., Hokkaido to Kyusyu (Table 1). Observations were made on certain characters of larval, pupal and adult stages of these local strains by rearing the insects under the condition of 25℃, of complete darkness and with an initial density of 20 larvae per vial. 2. In the 4th and 5th instar, the Tokyo and Kyoto strains showed higher values in the measurement of head width than those of the strains from the northern and the south-western localities (Fig. 1 and Table 2). 3. The larvae of the northern strains tended to be darker in their skin color and shorter in their larval developmental periods than those of the south-western atrains (Fig. 3). 4. The pupae of the Sapporo and Oita strains were less in weight than those of the Honsyu strains (Table 7). The ratio of the mean pupal weight to the mean length of larval duration was the largeat in the Sendai strain, and it decreased northward as well as south-westward (Fig. 4). 5. The pupae of the Sapporo strain were of non-diapausing, but those of the Honsyu and Kyusyu strains were a mixture of non-diapausing and aestivating types. Furthermore, both the non-diapausing and aestivating pupae of the south-western strains required longer time for pupal development than those of the northern strains (Fig. 5). 6. The sdults of the south-western strains were characterized by their longer life, and shorter duration of their oviposition period, as compared with those of the northern strains. Also, the female moths from the south-western localities deposited less numbers of eggs than those from the northern localities (Table 9).

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A previous checklist of the fishes of Sagami Bay, Japan, which included 1517 species belonging to 249 families (45 orders) recorded up to 2006, was revised using the following resources: fish collections of the Kanagawa Prefectural Museum of National History (KPM), the fish image database in KPM and literature records. The survey revealed 1934 species belonging to 284 families (43 orders) in the study area. Many of the species newly recorded in Sagami Bay are distributed mainly in waters south of the bay, which is likely to be closely linked to the transport of fishes by the Kuroshio Current. In addition, the recent rise in seawater temperatures in and around Sagami Bay due to global warming and other factors, may have allowed normally southern fish species to overwinter in Sagami Bay, thus leading to the significant increase in the number of species recorded over a relatively short period.

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クマノミ類が共生するイソギンチャクは，“宿主イソギンチャク”と呼ばれ，クマノミ類にとっての隠れ場所として重要な役割を果たしている。一方，“宿主イソギンチャク”にとってのクマノミ類の役割については，これまで曖昧な点が多かった。本稿では，まず，褐虫藻に注目した最近の研究をまとめ，クマノミ類との共生がイソギンチャクにもたらす利益について明確にした。このことにより，あるイソギンチャク1個体の着底後初期の生存と成長には，クマノミ類との潜在的共生種数が多いほど有利であろうと推察された。“宿主イソギンチャク”には，定着したクマノミ類のほとんど全てが繁殖場所として利用する種（4種）のほかに，定着したクマノミ類の中の特定の種のみが繁殖に利用する種（2種），ほとんど全てが繁殖場所には利用しない種（4種）があり，クマノミ類にとってのイソギンチャクの価値に格差が存在する。イソギンチャク1種にとってのクマノミ類の潜在的共生種数はそこで繁殖が確認されたクマノミ類の種数と極めて強く相関しており，クマノミ類が価値の高いイソギンチャクを選択的に利用する傾向が示唆される。“宿主イソギンチャク”は，クマノミ類との関係性，特に双方にとっての価値の高低に注目すると4タイプに類型化されるが，タイプ間で観察例数に大きな違いが見られ，地理的分布が重複する221例の組合せのうち，実在するのは37.1%（82例）であった。これまでの研究を概観することにより，実在する組合せには，1）“宿主イソギンチャク”とクマノミ類の地理的分布の重複のほかに，2）生息場所の一致，3）クマノミ類による宿主選択性，さらに，4）宿主をめぐるクマノミ類の種間競争が大きく影響していることが理解できる。クマノミ類よりも寿命が長く，浮遊幼生期間も長い“宿主イソギンチャク”の地理的分布には，暖流の影響が大きいことが文献情報の分析から明らかになった。“宿主イソギンチャク”の分類は日本では混乱しているが，多少の問題点があったとしても，世界で幅広く用いられている分類に従うことにより，日本近海で報告されているイソギンチャクとクマノミ類の分布や生態，関係性について，他海域で得られた知見との比較分析が可能となる。

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