ExcFIG 7B&C: Excretory canal.

B. Schematic rendering of a single canal located underneath the basal lamina of the hypodermis and in contact with the pseudocoelom on its basal surface. The canal makes extensive gap junctions to the surrounding hypodermis (thick black lines around the basal surface). The apical surface is surrounded by the terminal web (light gray line) on the cytoplasmic side and contains mucus (yellow line within lumen). Approximately 20 microtubules dot the cytoplasm.
C. TEM of a cross section of a single excretory canal. The canal lumen is surrounded by numerous small channels called canaliculi (arrowheads). The terminal web is seen as electron-dense material surrounding the lumen. (M) Mitochondrion. Bar, 1 μm. (Image source: [Hall] N506C.)

See also ExcFIG 7A .

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