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Conch Shells

The Fighting Conch (S. pugilis, Linn.), 3 to 4 inches long when full grown, is very common on the Florida coast, east and west. The spire is tapering, the whorls sculptured with fine parallel revolving grooves, the upper margin of each whorl set with sharp knobs. The aperture has an anterior and a posterior canal and a notch for the head in the broad outer lip near the tapering base of the shell. Outside, the pale colour of the shell is clouded with brown in bands or patches, often purplish, darkening on the body whorl. The shell lining is polished, as is also the columella. The lip is orange or deep red, shading back to purple, finally to pink.

The species exhibits considerable variability. Forms lacking the knobs on the shells have been described as a distinct species, alatus. Intermediate forms unite this smooth-shelled form as a variety to the species pugilis.

It is an exciting experience to watch these conchs on a Florida beach contriving to get back to the water after being stranded by the tide. One rarely sees in Florida such an illustration of strenuousness. The extended hook is struck into the wet sand, and over the shell rolls; the second stroke flings it in another direction. You can see the radula working rapidly as the proboscis is lifted. Obstacles are avoided, corners are turned, wherever possible the conch makes a leap, and at last plunks joyfully into the water. Not seldom does a handsome specimen escape the amazed collector by jumping out of the boat.

This handsome "molluscan buzzard," with all its pugnacity, accommodates within its shell a little crab, named by Miss Rathbun, Pinnotheres strombi. Perfect amity seems to exist between them. The mutual advantage of this arrangement is not quite clear to me.

It is possible for northern aquariums to have fighting conchs as tenants. Live specimens have been shipped to Philadelphia in no better wrappings than newspaper, surviving the long journey to be studied for months in a jar of sea water. It is true, however, that the exiles refuse food. At least this is the experience of one student. He made every effort to supply them.

The Hawk Wing Conch (S. costatus, Gmel.), found in the West Indies, is 5 to 6 inches long, a heavy ovate shell whose short sharp-pointed spire is decorated on all its whorls with blunt knobs, those on the body whorl very large. The lip is thick and dilated, tapering at both ends. The lining is white or reddish. It requires some effort to see the resemblance to a hawk's wing in the expanded lip of this shell.

The Angel Wing Conch (S. gallus, Linn.), 4 to 6 inches long, has a long, channeled finger considerably higher than the elongated, knobbed spire. The shell has a long curved basal stem and the lip flares widely. The exterior is ridged spirally and marked with blotches of orange brown. The aperture is tinged with the same colour. S. auris-Dianae has a similar form.

Habitat.--Red Sea.

The other species range from the size of a cocoanut to less than an inch long. They vary from the stout ovate shape of average conchs to slender spindle shape on one hand and typical cone shape on the other. High colouring is common. All tropical seas have their representatives. Yet the largest, finest and most prolific species of the genus live in the West Indies.