microscopic spirals crossed by fine growth-lines; suture deeply and widely channelled (about 1 mm. wide in a shell of 10 mm. diam.); aperture semilunar, narrower above; outer lip slightly concave, retracted to suture above; inner lip with thin enamel on parietal wall; umbilicus widely open, bounded by low ridge outside which is broad suleus caused by notch in anterior margin of aperture; on umbilical side of this notch is a thickening of margin which gives rise to ridge. Holotype in collection of Mr. R. S. Allan. Height, 11 mm.; diameter, 10 mm. Localities.—Greensand, Waihao Downs. (type); 164, greensand above coal-beds, Kakahu. Sulconacca compressa n. sp. (Plate 57, fig. 3.) Shell rather small, ovate, with compressed sides; spire gradate, about one-half the height of aperture; whorls 5, with microscopic spirals crossed by fine growth-lines; suture channelled (about 0.75 mm. in a shell of 10 mm. diameter); aperture ovate; outer lip slightly concave and gently retracted to suture, inner lip with thin enamel on parietal wall; umbilicus narrow, bounded by low ridge and shallow furrow. Holotype in collection of Mr. H. J. Finlay. Height, 11 mm.; diameter, 9 mm. Locality.—7c, Clifden. This species is distinguished from S. prisca by its more compressed shape, slightly narrower channel, ovate aperture, narrow umbilicus, and weak circum-umbilical sulcus. Sulconacca vaughani n. sp. (Plate 57, fig. 4.) Shell of moderate size, globose, robust; spire gradate, from one-half to two-thirds the height of aperture; whorls 6; protoconch of two smooth convex whorls with minute nucleus and with impressed suture which changes suddenly to à channelled one at commencement of the neanic shell; sutural channel when shell is 10 mm. in diameter is from 0.3 mm. to 0.5 mm. wide and about half this in depth; whorls smooth and polished, with some fine spirals crossed by inconspicuous growth-lines; aperture semilunar; outer lip straight, not retracted to suture except from bottom of channel, inclined about 20° from vertical; inner lip with relatively thick callus on parietal wall, thin and sharp on umbilical wall, then thickened again below; umbilicus moderate, bounded by furrow of variable depth which meets anterior margin of aperture at a shallow notch; on inner side of furrow is a more or less prominent ridge or basal limb. Holotype in collection of New Zealand Geological Survey. Height, 14.5 mm.; diameter, 12 mm. Localities.—1161, Pakaurangi Point (type); 166, Mount Horrible, Pareora River; Otiake beds, Trig. Z, Otekaike; 1172, Pukeuri, Oamaru; uppermost Mount Brown beds, Weka Pass [= N. auslralis (in part) of Suter, 1921, p. 43]; 882, sandy claystone above limestone, Waitomo Valley; 862, argillaceous sandstone, head of Waimata River; uppermost Mount Brown beds, Weka Pass (J. A. Thomson); Target Gully, Oamaru; Rifle Butts, Oamaru; Awamoa; 4b, 6a, 6c, Clifden, Southland (H. J. Finlay); Ardgowan; 1144, Okoko Road, one mile west of Pehu Trig., Upper Waitara; 1142, near junction of Tangitu Stream and Waitara River (L. I. Grange). Distinguished from suturalis by its large size, slightly narrower sutural channel, and straight outer lip not retracted to suture except from bottom