In an adult animal, each LE contains more than a thousand ommatidia consisting of a conical lens below which are located 5-12 photoreceptors, also called retinular
cells, arranged like the sections of an orange.
Retina.--The nearly hemispherical retina is composed of a layer of epithelial retinular
cells containing basally (or peripherally) located nuclei with a distinctive arrangement of heterochromatin (Fig.
Spectral sensitivities of retinular
cells measured in intact, living flies by an optical method.
argus eyes contain two spectral classes, with visual pigment in the cells of the main rhabdom (R1-7) absorbing maximally at 510 nm and pigment in the eighth retinular
cells (R8) at 370 nm (Cummins et al., 1984).
Short wavelength pigments are sometimes not seen in microspectrophotometry because they only occur in the eighth retinular
plebs, which has about 260 ommatidia with the five retinular
cells per rhabdom typical of other amphipods (Hallberg et al., 1980).
The pigment cells are shaped to form three cups, and within each cup are two to six photoreceptors, termed retinular
cells (Kauri, 1962; Walley, 1969; Walker et al., 1987; Clare and Walker, 1989).
Polarized light responses from retinular
cells and sustaining fibers of the mantis shrimp.
amphitrite cyprid, the nauplius eye is composed of three pigment "cups" (two lateral and one ventral), with each cup containing four retinular
To determine the rhabdom volume density, rhabdom areas were measured on micrographs of transverse and longitudinal sections of the retinular
cell layer and recorded as a proportion of the total area.
) cells were also labelled, but much less intensely than eccentric cells (9).
(Bursey, 1975; Gaten, 1994) - a distal retinula cell (R8) with four cytoplasmic lobes occupies the tier between the crystalline cone and the seven regular retinular
cells, but in Paralomis an ommatidial retinula is composed of only seven regular cells (1-7) and lacks the distal eighth cell.