ISSN:
1432-1793
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The entire process of development from eggs to juveniles was observed in the sea-star Ctenopleura fisheri Hayashi. The breeding season of this sea-star in Toyama Bay, the Sea of Japan, occurs in the winter. The eggs are 465 μ in diameter, semitranslucent and pale brown in color. They develop into a barrel-shaped larva, neither bipinnaria nor brachiolaria, through a wrinkled blastula stage by holoblastic, radial cleavage. Larvae are free-swimming and do not feed during the larval stage. At metamorphosis the stalk, a larval organ, disappears by one of either 2 different processes; absorption into future body of the juveniles, or rupture and collapse. Fifteen days after insemination, metamorphosis is completed and the resulting juveniles, about 1 000 μm in diameter, bear 2 pairs of tube-feet and a terminal tentacle in each arm.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00397194
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