ISSN:
1432-0878
Keywords:
Sense organs
;
Eyes
;
Opisthobranchs
;
Ultrastructure
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary The retina of nudibranch eyes contains two types of large cells; pigment cells which comprise about two-thirds of the total, with unpigmented sensory cells making up the remainder. Both pigment and receptor cells carry microvilli on their distal borders, but no traces of cilia were observed among them. The cornea of the eyes of aeolid and dendronotid nudibranchs is composed of a single layer of small cells, unlike the dorids where the cornea is made up of one of more large cells. The latter contain nuclei comparable in size with those of the pigment cells in the retina, but are themselves unpigmented. The elliptical eyes ofAplysia contain three types of retinal cell; the pigment cells and two kinds of receptor cells. The “ciliary” receptor cells bear equal numbers of cilia (9+2) and microvilli, while the “microvillous” receptor cells carry long tufts of microvilli with only an occasional cilium among them. The proximal cytoplasm of the receptor cells inAplysia and the nudibranchs contains large quantities of the small spherical vesicles (averaging 660 Å in diameter) which appear to be characteristic of gastropod eyes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01027719
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