8. THE LATERAL LINE ORGAN MECHANORECEPTOFS
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C. Epidermal Organs
The epidermal organs in Necturus maculosus are arranged in so-called
“stitches,” comprised of groups of 2 5 neuromasts (Fig. 7). Each neuromast contains 6-10 hair cells which reach with their apical ends to the
bottom of a shallow pit from which the tall and cylindrical cupula extends
for about 150 p (Fig. 8 ) . Hair cells in this animal are unusually large,
probably because of the large size of the nucleus; cytoplasmic organelles
are of ordinary size. As in Xenopus (Murray, 1955) each stitch is innerFig. 6. Adjacent to the sensory area is a secretory epithelium where openings
lead to goblet cells or glands.