著者

長谷川 和

出版者

日本動物学会

雑誌

動物学雑誌 (ISSN:00445118)

巻号頁・発行日

vol.62, no.6, pp.206-211, 1953-06

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By heat-treatment (for 5-40 minutes at 25-34℃) of fertilized eggs of the toads, Bufo vulgaris formosus (Boulenger), four double-headed tadpoles, which lived more than 30 days, were obtained. Generally in the head portions of these animals the organs were formed doubly, while in the tail portions singly; and intermediate forms of the two portions were recognized in the trunk portions. It may be considered that these animals were produced by the division of the direction of primary invagination.