CYLICHNA. 315 



This is evidently not the Cylichna strigella of Loven, which is a 

 synonym of Retusa umbilicata. 



C. DECUSSATA A. Adams. PI. 27, fig. 82. 



Shell small, subcylindrical, elongated, slightly dilated at the 

 base, white, crossed with longitudinal and transverse strise ; spire 

 conspicuous, immersed in the umbilicated apex, peromphalus radi- 

 ately striated ; aperture narrow, linear, produced superiorly, dila- 

 ted below ; columella simple (Ad.~). 



China Sea (Cuming) ; Suez (Cooke) ; Darnley Island, Torres 

 Strait (Brazier). 



B. (Cylichna) decussata AD., Thes. p. 594, pi. 125, f. 147. Oy- 

 liclma decussata COOKE, Ann. Mag. N. H. (5), xvii, p. 128. BRA- 

 ZIER, P. L. S. X. S. W. ii, p. 80. 



C. BRAZIERI Pilsbry, n. n. Unfigured. 



Shell cylindrical, small, white, thin, contracted in the middle, 

 longitudinally and transversely rugosely striated ; whorls 3j, apex 

 umbilicated, deep ; aperture narrowly linear, peristome thin, con- 

 tracted in the center, slightly produced above, expanded below, 

 columella thickened, straight, slightly reflected. Length 1}, diam. 

 at base I, above the center line (BrazJ). 



Darnley Island, Torres Straits, 30 fathoms. 



Cylichna minuta BRAZIER, Proc. Linn. Soc. N. S. Wales, ii, p. 

 80, i877. Not C. minuta H. Adams, 1872. 



Two specimens found. The apex of this beautiful little species is 

 quite depressed or truncated, and the umbilicus of the apex, sunk 

 deep down ; somewhat allied in sculpture to C. decussata (Braz.~). 



C. CRISPULA Watson. PL 30, fig. 12. 



Shell narrowly oblong, more contracted above than below, with 

 the greatest breadth below the middle, obliquely truncate above and 

 below, thin, translucent, glossy, very faintly spirally striate all 

 over ; the top is like that of a Volvula, but beside the prominent 

 lip the axis is perforated ; there is a strong pillar tooth. Sculpture : 

 Longitudinals the lines of growth are very slight and unequal. 

 Spirals the whole surface is covered with very slight, superficial 

 fretted, rather unequal, and somewhat remote furrows. Colour trans- 

 lucent glossy milk-white. Mouth long and narrow above, rising and 

 retreating at the top of the shell, widening in front, but not very large 

 even there. Outer lip rises from the edge of the axial pore, and 



