304 CYLICHNA. 



C. semisulcata DKR., Index Moll. Mar. Jap., p. 163, pi. 13, f. 7-9. 



0. japonica A. Ad. is certainly similar, but seems to differ in 

 being transversely sulcate throughout, and lacks the close longitu- 

 dinal wrinkles. 



C. JAPONICA A. Adams. Unfigured. 



Shell cylindrical, rimate-umbilicate, usually covered with a thin 

 brown epidermis, rounded at both ends; apex perforated, trans- 

 versely very delicately striated throughout, the striae more distant in 

 front. Aperture linear, dilated in front ; inner lip thin, elongated, 

 simple ; outer lip rather straightened, strongly produced and roundly 

 angled behind. (Ad., Ann. Mag. Nat. Hist. (3), ix, p. 150, Feb., 

 1862). 



Korea Strait, 46 fms. 



Next to C. arachis Quoy, which was likewise obtained in the 

 Korea Strait, this is the largest species of Cylichna, it differs from 

 that species in being more elongated and less robust ; and in the 

 angle of the outer lip being produced and angulated, extending con- 

 siderably beyond the apex. (Ad.*). 



C. PROXIMA A. Adams. Unfigured. 



Shell ovate cylindrical, rounded at the ends, white, solid, shining, 

 subopaque, transversely very minutely striated throughout ; apex 

 profoundly umbilicate ; aperture linear, constricted in the middle, 

 dilated anteriorly, inner lip furnished with a thick oblique fold ; 

 outer lip straight in the middle, arcuate in front, posteriorly subpro- 

 duced and rounded. (Ad., LJZ., p. 151, no. 2). 



Tsu-Sima, Japan, 26 fathoms. 



Resembles C. sarsii Phil. ; but the aperture is constricted in the 

 middle ; it is also like C. concinna A. Adams, but is stouter and not 

 produced anteriorly, and the angle of the outer lip is rounded. 

 (Ad.-). 



C. VENUSTULA A. Adams. Unfigured. 



Shell ovate-cylindrical, somewhat narrowed at each end, white, 

 rather solid, shining, transversely very finely striated throughout, 

 the apex perforated. Aperture linear, dilated in front ; inner lip 

 arcuate, with an oblique fold, slightly truncated below ; outer lip with 

 regularly arcuate margin. (Ad., 1. c., p. 151, no. 3). 



Mino-Sima, Japan, 63 fathoms. 



