Retusa Waughiana, sp. nov.

(Fig. 44).

Fig. 44

Shell subcylindrical, swollen below, sharply truncated above, produced and rounded an teriorly. Colour porcelain white, glossy. Sculpture—longitudinal, irregularly spaced ribs traverse the whole shell, anteriorly they are weak threads, posteriorly they wax stouter and form tubercles as they obliquely mount the vertex. Between these the shell is closely girt by about forty spiral grooves and their complementary ridges. Whorls four, the earlier ascending, the last descending. Suture deeply channelled. Apex mamillate, rising above the crown. Aperture very oblique, racquet shaped. Outer lip springing from the wall considerably below the vertex, rounded posteriorly, parallel with the body whorl as far page 483as the waist of the shell, then curving outwards. Columella broad, sinuate, folded over a slight umbilical chink. Callus on body whorl distinct, forming a decided angle posteriorly. Length 1¾, breadth 1 mm.

Three specimens from the lagoon beach.

This species perhaps stands nearest to R. amphizosta, Watson,^* from which it is easily distinguished by the even more puffed anterior half, the descent of the last whorl, and by the coarser, more prominent sculpture. The young shells differ altogether in contour from the adult, but may be recognised by their peculiar sculpture.

This novelty is named in honour of my accomplished friend, Lieutenant A. Waugh, R.N., of H.M.S. "Penguin," who, during the Expedition to Funafuti, as on many previous occasions, afforded his hearty aid and sympathy to every scientific undertaking.