. . .s by means in some cases of a shelly secretion, but more usually by cementing bits of shell, stones, and grains of sand into an irregular tube lining the burrow; the slender, limy serpentine tubes often seen on stones or dead shells in tide pools, are, or were, the homes of such protected worms, most commonly of the "shell worm" (Serpula). "Often a number of these calcareous worm tubes are seen clustered together.[Pg 55] When undisturbed the worm protrudes its beautiful feathered gills, which resemble a little passion flower projecting from the mouth of the tube. These gills are variously colored in different individuals, some being purplish brown, banded with white and yellow, while others are yellowish green, orange, or lemon-yellow. At the least disturbance, such as a shock or a shadow, the gills are instantly withdrawn into the stony tube, and the opening stopped by a horny disk." In the Gulf of Mexico extensive colonies of these worms often form, and as the ear. . . Read More