Animal having an asymmetrical cephalic region, the left epipodial lobe usually absent; there are 4 eplpodial tentacles on each side. No jaws. Radula with the central tooth broadly oval and a small reflection, narrow or broad, sometimes minutely denticulate ; the 5 lateral teeth increasing in size from the centre outwards ; they have a broad reflection with an inner stout cutting-point and 2 to 3 fine denticles on the outer side ; uncini with a strong pointed tooth.
Shell imperforate or perforate, conoidal, subdepressed, whorls smooth, generally polished and with fine spiral lines. Aperture large : outer lip sharp ; inner lip strongly callous and usually spreading outward and more or less covering the narrow umbilicus. Operculum multispiral.
Distribution.—Austral seas.
Remarks.—Thiele included in his genus Margarella our species P. nitida and P. antipoda because the dentition shows a close resemblance. Margarella stands, no doubt, nearer to Valvatella, the animal having jaws.
Type : P. coerulescens, King