The Egg Shells - Family Ovulidae
THE EGG SHELLS - FAMILY OVULIDAE. Shell involute, body whorl covering the spire, smooth, porceflanous, whitish or dull in colouring; aperture long, its extremities usually drawn out to form two canals; inner lip smooth, outer usually ridged, bent inward; foot large; mantle reflected over shell when in use. One genus of fifty species in warm seas.
Genus OVULA, Brug.
The egg shells are close to the cowries in structure and habits. Unlike them, the spire of the shell is concealed from the first, and the columellar lip is rarely toothed. The egg form is modi fied by the two terminal canals.
The Swollen Egg Shell (0. gibbosa, Linn.), somewhat over an inch long, has a thick shell, blunt at the ends, highly polished, with brown clouding on a pale ground. The lips are thick and free from teeth. A swollen band encircles the shell midway between the ends.
Habitat.— Florida.
0. acicularis, Lam., is very smooth,slender and thin; colour, purplish or yellow. It is found closely attached to stems of sea fan. Length, inch.
Habitat.— South Carolina, Florida, West Indies.
0. uniplicata, Sby., of similar habits, colour, shape and size, is distinguished by a distinct fold on the columella near the posterior end of the shell. Length, inch.
Habitat.— North Carolina to Florida, Southern California.
The Californian forms are purple or violet, with pale lips. In the southeast there are two solid colours, yellow and purple, as in the sea fans on which this mollusk lives. If a yellow fan, then it will require sharp eyes to find the yellow shells closely applied to the stems. If the fan is purple, the shells are purple.
135 The Egg Shells The Great Egg Shell (0. ovum, Linn.) is as large as a goose egg, white, tapering from its swollen middle to the blunt, canali culated extremities. The animal is black, with stout tubercles
covering its reflected mantle lobes. The shell lining is brown. The lip is incurved and wavy toothed.
The Pacific Islanders in holiday attire have these white egg shells hanging from elbows, wrists, ankles and belts. They use them very effectively in decorating their canoes, houses and temples.
A similar, but smaller species, 0. tortilis, Martyn, with rose-coloured lining, comes from Zanzibar and the Friendly Islands.
0. volva, Linn., has a canal at each end as long as the oval shell, making a total length of from three to five inches. The exterior is crossed by remote striations. The colour is a brownish flesh colour.
Habitat.— China, Japan, Philippines.
The Poached Egg (0. patula), the little English species, is yellow, fading into white. It lives among colonies of zoophites, resembling our slender thin-shelled species of the Southeast.
The valuable cargoes of sandal-wood obtained in some of the Pacific islands for the China market are, in the first instance, purchased from the New Hebrides by means of a shell — the Ovulum angulosum, a white, porcellaneous variety of cowry with a violet-coloured lip —which is found in the Friendly Islands, but never in the sandal-wood region. This shell is so highly esteemed as an ornament by the natives of the New Hebrides that for one shell they will give in exchange a ton of sandal-wood. The trading captains go expressly to the Tongan archipelago for the shells, where they sell at a Spanish dollar each.—Szmmonds.
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