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Scallops — Part 2

This species is rare in collections, even on its native coasts. Storms that drive inshore with unusual force may throw a few on the beach. Diameter, 3 inches.

Habitat.--Europe, New England.

The Magellan Scallop (P. Magellanicus, Gmel.) is the largest American species. Though found only in northern waters it has been confused with a Patagonian species, and the name clings The valves are circular and dissimilar, gaping in front of the large, almost equal ears. The surface of the valves bears a great number of uniform radiating ridges, crossed and roughened by fine, upturned scales. The left valve is rose-coloured, deepening toward the beak. The flat right valve is almost white. A deep water species. Diameter, 5 to 6 inches.

Habitat.--Newfoundland to New Jersey.

The Beaming Scallop (P. irradians, Lam.) is the most common species on the Atlantic coast, the edible scallop usually sold in our seaboard cities. Tons are dredged from the Jersey banks annually, and the demand is increasing. The shells sell also for "scalloping" shell fish, and for making fancy articles.

The outline of the valves is almost circular, with prominent, almost equal ears. The surface bears about twenty high, rounded ribs, separated by rounded grooves. The exterior is brown, with concentric pale zones and radiating bars of red, purple or orange. A medley of rich colours is not uncommon. The lining is white and polished. A shallow water species. Diameter, 2 to 3 inches.

Habitat.--New England to Cape Hatteras.

P. dislocatus, Say, replaces the preceding species below the Cape. Both its valves are convex, and set with close, rounded ribs. The ears are almost equal. The white ground is variously decorated with red or yellow in zigzag cross lines or in mottled designs. It occurs in a great variety of colors and patterns on the coast of Florida. In the shallow pools the young disport themselves, swimming about in gamesome mood. If frightened, they stir up the muddy bottom, and flee under the cloud that furnishes ample protection. Diameter, 1 to 2 inches.

Habitat.--North Carolina southward.

The Blunt-knobbed Scallop (P. subnodosus, Sby.) is the most ponderous living species, named for the obscure raised nodules on the strong ribs. The surface is sharply striated and dark purplish brown, cross-waved with white. Old specimens attain surprising thickness and weight. They are as large as P. maximus.

Habitat.--West coast of tropical America.

The Weather Vane Scallop (P. caurinus, Gld.) has flat, thin, very broad valves, with small ears, and about twenty low ribs. A very fragile, dark brown shell. Diameter, 5 to 6 inches.

Habitat.--Northwest coast.

The Pink Pecten (P. hericeus, Gld.) is white, rayed with pink; the cardinal ridges are toothed, and separated by wide channels. The ears are unequal. Diameter, 2 inches.

Habitat.--Washington to California.

The Speckled Scallop (P. oequisulcatus, Cpr.) has the symmetry of form, the even fluting and the various colouring and markings of the scallops of our warmer Atlantic coasts. Its scheme of colours leans toward shades of brown. Diameter, 2 to 3 inches.

Habitat.--Southern California.

P. Diegoensis, Dall, has a dark red, flattened upper valve, with twenty distinct ribs. The lower valve is yellow. Diameter, 3 to 5 inches.

Habitat.--San Diego, Cal., northward.

This large scallop has a companion in the Californian cap shell (Capulus Californicus, Dall) which clings to the under valve, at the left of the hinge, close to the byssal notch. White within, dingy brown and shaggy without, it may well be mistaken for a wad of dead seaweed clinging to the larger shell. It is about an inch and a half long.

P. distorsum, Da C., attaches itself inside the shell of another species. The under valve of the parasite becomes imbedded in the lining of its host's shell. We can imagine this arrangement involves much discomfort for both partners, as growth proceeds.

The Spear Scallop (P. hastatus, Sby.) is ovate, with comblike rows of spines on each of the ten most prominent ribs. These are worn off of the right valve. The colours are vivid; red, purple and yellow in different shades are seen. Free-swimming forms, alike on both valves, and spineless, are local forms. The young are spineless.

The animal alive in an aquarium shows not only the beauty of its rosy shell set with rows of spears. The body is a rich orange colour, set on the mantle margin with black eyes. The flesh is so transparent that the action of the heart and other organs can be seen by removing one valve. Young specimens can attach themselves at will to the stems of seaweed. Thus they rest when tired of swimming.

This deep sea species seems to correspond in its characters to P. Islandicus. Diame. r, 1 to 2 inches.