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Observations on the Gymnosomatous Pteropod Clione Limacina (Phipps)

Published online by Cambridge University Press:  11 May 2009

J. E. Morton
Affiliation:
Department of Zoology, Queen Mary College, University of London

Extract

Some features of the digestive and reproductive systems, as well as the habits and swimming of the pteropod Clione limacina have been studied from specimens of the dwarf ‘southern’ race, which occurs at Plymouth. The animal swims rapidly by the sculling action of its two short rounded ‘wings’ or parapodia. Its buccal mass is characterized by specialized prehensile organs, consisting—as well as the radula—of adhesive tentacles (cephaloconi) and a pair of hook sacs. The rest of the gut is simple, consisting chiefly of a ‘stomach’ formed by two spacious digestive diverticula, that have replaced the true stomach. The lining includes absorbing-digestive cells and excretory cells. C. limacina is a protandrous hermaphrodite. The size distribution of a sample of 338 is shown. The youngest specimens are all males; in older groups developing oocytes are found, and in the largest are eggs not yet ready for shedding (September), as well as sperms. The genital tract is of the primitive opisthobranch form, with a sperm-storing hermaphrodite duct, albumen gland and mucus gland. An external seminal groove leads forward to the penial sheath in the head. The structure of the penis and prostate is described, and some previous views on the nature and functioning of these parts are criticized. Finally, the relationships of the gymnosomatous and thecosomatous pteropods are briefly reviewed, and the use of separate orders is recommended in place of the recently revived single group Pteropoda.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 1958

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References

REFERENCES

Boas, J. E. V. 1886. Zur Systematic und Biologie der Pteropoden. Zool. Jb., Bd. 1, pp. 311–40.Google Scholar
Eales, Nellie B. 1921. Aplysia. Mem. Lpool mar. biol. Comm., No. 24, 92 pp., 7 pl.Google Scholar
Eschricht, D. F. 1838. Anatomische Untersuchungen üuber die Clione borealis. Kopenhagen. 65 pp.Google Scholar
Fretter, Vera 1942. The genital ducts of some British stenoglossan prosobranchs. J. mar. biol. Ass. U.K., Vol. 25, pp. 173211.CrossRefGoogle Scholar
Hoffmann, H. 1939. Opisthobranchia (part 7). Bronn's Tierreich, Bd. 3, Abt. 2, Buch 3, Lief. 7, pp. 1105–247.Google Scholar
Kwietniewski, C. 1903. Contribuzione alia conoscenza anatomo-zoologica di Pteropodi Gimnosomi di Mare Mediterraneo. Ric. Lab. Anat. norm. Univ. Roma, Vol. 9.Google Scholar
Lebour, Marie V. 1931. Clione limacina in Plymouth waters. J. mar. biol. Ass. U.K., Vol. 17, pp. 785–95.CrossRefGoogle Scholar
Lemche, H. 1948. Northern and Arctic tectibranch gastropods I-II. Kgl. Danske Selsk. Biol. Skr., Vol.5, (3).Google Scholar
Meisenheimer, J. 1905. Pteropoda. Wiss. Ergebn. 'Valdivia', Bd. 9, pp. 314.Google Scholar
M'Intosh, W. 1898. Notes from the Gatty Marine Laboratory, St Andrews. I. On the larval stages of Clione limacina. Ann. Mag. nat. Hist., Ser. 7, Vol. 2, pp. 103–5.CrossRefGoogle Scholar
Morton, J. E. 1954. The biology of Limacina retroversa. J. mar. biol. Ass. U.K., Vol. 33, pp. 297312.CrossRefGoogle Scholar
Morton, J. E. 1955. The functional morphology of Otina otis, a primitive marine pulmonate. J. mar. biol. Ass. U.K., Vol. 34, pp. 113–50.CrossRefGoogle Scholar
Morton, J. E. & Holme, N. A. 1955. The occurrence at Plymouth of the opistho-branch Akera bullata, with notes on its habits and relationships. J. mar. biol. Ass. U.K., Vol. 34, pp. 101–12.CrossRefGoogle Scholar
Odhner, Nils HJ. 1939. Opisthobranchiate Mollusca from the western and northern coasts of Norway. K. norske vidensk. Selsk. Skr., No. 1, 93 pp.Google Scholar
Pelseneer, P. 1885. The cephalic appendages of the Gymnosomatous Pteropoda, and especially of Clione. Quart. J. micr. Sci., Vol. 25, pp. 491509.Google Scholar
Pelseneer, p. 1888. Report on the Pteropoda collected by H.M.S. Challenger. III. Anatomy. Rep. 'Challenger', Vol. 23, 132 pp.Google Scholar
Pelseneer, P. 1906. Mollusca. A Treatise on Zoology, ed. E. Ray Lankester, Vol. 5. London.Google Scholar
Pruvot-Fol, A. 1926. Mollusques ptdropodes gymnosomes provenant des campagnes du Prince Albert I de Monaco. Result. Camp. sci. Monaco, Fasc. 70, pp. 160.Google Scholar
Pruvot-Fol, A. 1954 Mollusques opisthobranches. Faune Fr., No. 58, 460 pp.Google Scholar
Tesch, J. J. 1950. The Gymnosomata. II. Dana Rep., Vol. 36, pp. 155.Google Scholar
Thiele, J. 1931. Handbuch der systematischen Weichtierkunde. Bd. 2. Jena.Google Scholar
Wagner, N. 1885. Die Wirbellosen des Weissen Meeres. Leipzig.Google Scholar