Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-17T23:32:20.821Z Has data issue: false hasContentIssue false
  • English
  • Français

The ciliary feeding mechanism of the cyphonautes larva [Polyzoa Ectoprocta]

Published online by Cambridge University Press:  11 May 2009

D. Atkins
D. Atkins
Affiliation:
From the Plymouth Laboratory
Get access Rights & Permissions [Opens in a new window]

Extract

The cyphonautes larva found in certain ectoproct Polyzoa is considered to be most probably a primitive larval form, which has been lost in viviparous species, the larvae of which are degenerate in varying degree and settle within a short time. The cyphonautes is truly planktonic and has a free swimming Life of some length—of 2 months according to Marcus (1940, p. 334)—and unlike the other known larvae of the group, has a functional alimentary canal. It obtains its food by maintaining a continuous current of water through the mantle cavity or vestibule, its ciliary mechanism being organized on a plan somewhat resembling that of bivalve molluscs, with an inhalant and an exhalant chamber with interposed ciliary ridges bearing current-producing and food-conveying cilia. As in lamellibranchs the organ creating the water and food currents is separated by a considerable interval from the mouth. In lamellibranchs this interval is bridged by the palps and the oral grooves; in the cyphonautes by the ciliated tract of the funnel. The cyphonautes being a larval form of probably archaic character its method of feeding is of particular interest.

Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 34 , Issue 3 , October 1955 , pp. 451 - 466
Copyright
Copyright © Marine Biological Association of the United Kingdom 1955

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Atkins, D., 1938. On the ciliary mechanisms and interrelationships of lamellibranchs. Pt. VI. Quart. J. micr. Sci., Vol. 80 pp. 331–44.Google Scholar
Atkins, D., 1955. The cyphonautes larvae of the Plymouth area and the metamorphosis of Membranipora membranacea (L.). J. Mar. biol. Ass. U.K., Vol. 34, pp. 441–9.CrossRefGoogle Scholar
Claparède, A. R. E., 1863. Beobachtungen über Anatomie und Entwicklungsgeschichte Wirbelloser Thiere an der Kiiste von Normandie Angestellt. Leipzig.Google Scholar
Devèze, L., 1953. Contribution à l'étude de la nutrition des stades larvaires planctoniques. I. Rec. Trav. Sta. Mar. Endoume, Fasc. 8, pp. 49–54.Google Scholar
Ehrenberg, C. G., 1838. Die Infusionsthierchen als Vollkommene Organismen. Leipzig. 2 vols.Google Scholar
Knight-Jones, E. W., 1954. Relations between metachronism and the direction of ciliary beat in Metazoa. Quart. J. micro. Sci., Vol. 95, pp. 503–21.Google Scholar
Kupelwieser, H., 1905–1906. Untersuchungen über den feineren Bau und die Metamorphose des Cyphonautes. Zoologica, Stuttgart. Heft 47 (= Bd. 19, Lfg. 4), pp. iv + 50.Google Scholar
Marcus, E., 1940. Mosdyr (Bryozóa eller Polyzóa) in Danmarks Fauna, Vol. 46, Kobenhavn.Google Scholar
Prouho, H., 1892. Contribution à l'histoire des Bryozoaires. Arch. Zool. exp. gén., Ser. 2, T. 10, pp. 557–656.Google Scholar
Robertson, A., 1908. The incrusting chilostomatous Bryozoa of the west coast of North America. Calif. Univ. Publ., Zool., Vol. 4, pp. 253–344.Google Scholar
Schneider, A., 1908. Zur Entwickelungsgeschichte und systematischen Stellung der Bryozoen und Gephyreen. Arch. mikr. Anat., Bd. 5, pp. 260–80.CrossRefGoogle Scholar