Philippine Archipelago; Island of Bantayan. Attached to a horny coralline: 20 fathoms. Mus. Cuming.

HERMAPHRODITE.

Capitulum, with the upper part narrow and produced.

Valves, 15 in number, placed close together, clouded pale red, covered with membrane, which is thickly clothed with minute points.

Scuta rather small, oval, with the upper end pointed; rather convex; basal and lateral margins blending into each other; the upper produced portion above the umbo is small; there is a deep pit for the adductor muscle, and there is a fold on the occludent margin in the usual position; occludent margin not straight.

Terga large, one third of their own length longer than the scuta; fat, sub-triangular; the three margins are not quite straight; the carinal margin projects a little above the apex of the carina, and the scutal margin is excised to fit the upper part of the scuta.

Carina bowed, internally deeply concave; upper portion above the umbo, about one fourth of the total length, extending between the terga for two thirds of their length, up to the slight prominences on their carinal margins: a ridge separates, on each side, the parietes from the tectum.

Rostrum ([fig. 7 a]) unusually large, about two thirds of the length of the scuta, and twice as long as the rostral pair of latera; internally concave, externally carinated; outline of the upper portion acutely triangular, of the lower portion rounded; umbo seated at the upper end.

Upper Latera pentagonal, with the apex rounded.

Rostral Latera flat, four-sided, with the basal margin the longest, and the baso-carinal angle produced.