著者

浜田 啓吉

出版者

公益社団法人 日本水産学会

雑誌

日本水産学会誌 (ISSN:00215392)

巻号頁・発行日

vol.19, no.2, pp.79-82, 1953-06-25 (Released:2008-02-29)

参考文献数

7

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The pond smelt, Hypormesus olidus (PALLAS), migrates inherently into the sea and ascends for spawning to streams, but the land-locked form also occurs commonly in lakes and pond in Japan. The studies on the land locked-form of Main Land of Japan have been carried out by F. MATSUZAKI, ('36) and T. FUJITA, & S. KOKUBO, ('26), I AMEMITA & Y. HIYAMA, ('31), H. KOBAYASHI ('36) and K. MATSUBARA, ('46). However, nothing has been studied on the fish which ascends in fresh water from the sea. Of the fishes of the River Ishikari, the school of the present waterway which ascends from the sea differs from the fish of the old waterway in the morphological characters such as the body length, the scale structure and the number of vertebrae. Consequently, each school of both waterways is independent ecologically with each other, The fish of the present waterway migrates into the sea, while the school of the old waterway stays through the life in fresh water, in spite of the presence of passage to the sea.

著者

浜田 啓吉

出版者

公益社団法人 日本水産学会

雑誌

日本水産学会誌 (ISSN:00215392)

巻号頁・発行日

vol.19, no.2, pp.75-78, 1953-06-25 (Released:2008-02-29)

参考文献数

8

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The scale of pond smelt, Hypomesus olidus (PALLAS), shows no definite annual-ring in such a manner as the scale of salmon or herring. Two different zones, one of which grows in summer and the other in winter, are recognized on the scale of the fish in Lake Kasumigaura by F. MATSUZAKI (1916), while, according to H. KOBAYASHI (1936), the fish of Lake Shironuma shows the spawning mark which may probably be formed by the spawning. The present study aims to find the local difference of scale structures of pond smelts. The fishes of three localities of Hokkaido, the anadromous type of the river Ishikari, the land-locked-form Lake Junsai and the fishes of Lake Abashiri connecting with the sea, were taken up as the materials under three different ecological conditions. The marks on the scales of pond smelt from Lake Abashiri (Fig. 3) ought to be thought as the spawning mark, but those of the fishes of Lake Junsai (Fig. 5) are the interstitial mark bet-ween the winter and summer zones, and the material from the River Ishikari (Fig. 1) lacks these marks. There, the scales of pond smelts differ with their localities and appear the different cha-racteristic structure.