A cormidium may contain a single nutritive siphon (" monogastric ") or several siphons (" polygastric ").
Siphons are sometimes used to carry the water over an undulating grade and thereby save the expense of a deep rock cutting.
In the former will be found such things as siphons," Hero's fountain," penny-in-theslot "machines, a fire-engine, a water-organ, and arrangements employing the force of steam.
Mantle closed to a considerable extent; siphons well developed; gills much folded and frequently prolonged into the branchial siphon.
In the Mississippi valley water is taken from the river by flumes in the levees or by siphons.