The fine structure of the eye and optic tentacle of the mollusc Cardium edule

doi:10.1016/S0022-5320(69)90055-0

Journal of Ultrastructure Research

Volume 26, Issues 5–6, March 1969, Pages 515-528

https://doi.org/10.1016/S0022-5320(69)90055-0 Get rights and content

The eye is composed of a reflector cup, inside which are cells whose photoreceptor surfaces are modified cilia. These cilia have a 9 + 0 internal filament content and arise from basal bodies that bear basal feet. Microtubules are attached to these basal feet, but roots are absent. The receptor cells bear axons. The likely functional connection of the ciliary nature of the receptor cells and their generation of a physiological “off” response is discussed. Other features of the tentacle described are the presence of ciliated cells at the apex of the tentacle that are probably olfactory receptors, the occurrence of pigment granules in the epithelium behind the eye, the arrangement of muscles and the structure of the motor end plates of these muscles, and the structure of the iridophores.

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The eyestalk of Cerastoderma edule (Linnaeus, 1758) shares great similarity with the scallop eyestalk, including an epithelium covered by microvilli, peripheral muscle bands, and a central nerve (Barber and Wright, 1969). In contrast to the ciliated epithelium of scallop pallial eyestalks, ciliated receptor cells of C. edule and Cochlodesma praetenue (Pulteney, 1799) are restricted to the tip of the eye-bearing tentacles (Barber and Wright, 1969; Morton, 2008). Pallial eyes also occur at the base of the tentacles, as in Ctenoides floridanus (Olsson and Harbison, 1953) (Limidae), in which the pigment cups are located at the base of the middle mantle fold tentacles (Morton, 2000).
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The fine structure of the eye and optic tentacle of the mollusc Cardium edule

J. Ultrastruct. Res.

J. Ultrastruct. Res.

J. Ultrastruct. Res.

J. Ultrastruct. Res.

J. Ultrastruct. Res.

J. Ultrastruct. Res.

J. Microscopie

Z. Zellforsch. Mikroskop. Anat.

Z. Zellforsch. Mikroskop. Anat.

J. Physiol. (London)

Experientia

Biol. Bull.

J. Cell Biol.

Z. Zellforsch. Mikroskop. Anat.

Compt. Rend. Acad. Sci.

Am. Zoologist

J. Cell Sci.

Mem. Osaka Gakugei Univ.

J. Biophys. Biochem. Cytol.

Biol. Bull.

J. Cellular Comp. Physiol.

Quart. J. microscop. Sci.

Biol. J. Okayama. Univ.

J. Gen. Physiol.

Compt. Rend. Acad. Sci.

Z. Zellforsch. Mikroskop. Anat.