260 
rato-conaliculate towards which the upper margin is 
suddenly inflexed ; mouth ovate, nearly half the whole 
length, peristome thin, columellar lip rather inflexed 
and terminating in a prominent plait on the columella ; 
no umbilicus. 0,06...0,02. Aberdeen. 
O. Marionz. Macg. Ab. p. 156. Ovate conical, 
hyaline white, thin, transparent, rather glossy : whorls 
five, finely plicated lengthways and delicately striated 
spirally, the upper margin of each in the form of a 
plaited rib; mouth ovate, nearly half the whole length, 
peristome slightly thickened, not reflexed on the pillar 
but ending in a very slight plait behind the minute um- 
bilicus. 0,04...0,02. Aberdeen. 
O. Annz&. Macg, Ab. p. 157. Oblong-turreted, 
rather thick, opaque, glossy, destitute of markings, pure 
white ; suture slight, whorls five, the body convex and 
proportionably large, the rest flattened ; mouth ovate, 
nearly a third ofthe entire length, peristome thin, its 
columellar portion rather inflexed and terminating in a 
small plait on the pillar opposite the small umbilicus. 
(),04...0,14. Aberdeen. 
O. Ostonea. Macg. Ab. p. 157.—Oblong, subcy- 
lindrica]. very slightly taperingand ending in an obtuse 
