Shell ovate, with sides subparallel and very slightly arched; anterior end broadly rounded, subtruncate. Pedicle-valve with umbonal edges diverging at about 110°. Interior of pedicle-valve with a large, elongated, subrhomboidal, thickened area extending for nearly half of the length of the valve and produced in front into a long, tapering point reaching to about three-fourths of the length of the valve; area defined by narrow raised ridges which arise near the beak, and run outwards and forwards on each side with increasing strength and slight curvature to the widest part of the area, thence curving inwards and converging, at first at about 60° and finally at a rapidly diminishing angle, to meet in a sharp point in the middle line. Concrete laterals narrow, triangular, extending for more than half of the length of the area, forming an elongated, subrhomboidal scar divided by a rather broad, rounded median groove continued forwards to the anterior point of the area; centrals transverse, oval, oblique, large, lying in front of and alongside of the concrete laterals, separated anteriorly by the median groove. Cardinal margin of valve somewhat thickened and flattened internally. Dimensions.—Length of valve = 26 mm. Width of valve = 19 mm. Length of area to tip=17 mm. Width (maximum) of area = 9 mm. Horizon and locality.—Woolhope Limestone, Littlehope. Remarks.—The internal characters of this shell are closely similar to those of L. lewisi Sowerby, from the Aymestry Limestone; but the internal area is more developed as a platform, the median ridge is