Cylichnella.] GASTROPODA. 531 



1. Cylichnella pygmaea, A. Adanis, 1850. Plate 23, fig. 3. 



Bulla (Cylichna) pygmcea, A. Ad., in Thes. Conch., ii, 595, pi. 125, f. 150. 

 Haminea pygmcea, A. Ad., A.M.N.H. (3), ix, 155. Cylichna pygmasa, 

 A. Ad., Man. Conch. (1), xv, 319, pi. 59, f. 9. Bullinella pygmcea, 

 A. Ad. : Tate and May, P.L.S. N.S.W., 1901, 416; Pritchard and Gatliff, 

 P.R.S. Vic. (n.s.), xv, 214. Cylichna Atkinsoni, T.-Woods, P.R.S. Tas., 

 1875 (1876), 156; Man. Conch., t.c., 318. C. pygmcea, A. Ad.: Murdoch 

 and Suter, T.N.Z.I., xxxviii, 279. 



Shell small, subcylindrical, slightly contracted in the middle, 

 apex umbilicated. white, shining, axially striated. Sculpture consist- 

 ing of subequidistant flexuous distinctly marked growth-lines, crossed 

 by dense and undulating fine microscopic spiral lines, more distinct 

 on the base. Colour white. Spire deeply sunken, top narrowly 

 funnel-shaped, with a relatively wide and deep perforation. The 

 body-whorl angularly rounded and ascending above, almost straight 

 at the sides, somewhat widened toward the base. Aperture as high 

 as the shell, very narrow above, much dilated below, and slightly 

 effuse at the base. Outer Up thin and sharp, produced above, in- 

 flexed at the middle, regularly rounded below. Columella very short, 

 straight, forming an imperceptible angle with the first flattish higher- 

 up .convex parietal wall. Inner lip narrow, spreading over the whole 

 height of the parietal wall. 



Diameter, 2 mm. ; height, 4-5 mm. 



Animal unknown. 



Type in the British Museum. 



Hob. Off Great Barrier Island, in 110 fathoms. Also Australia 

 and Tasmania. 



2. Cylichnella striata, Hutton, 1873. Plate 23, fig. 4. 



Cylichna striata, Hutt., C.M.M., 52 ; J. de Conch., 1878, 40 ; M.N.Z.M., 

 120; Murdoch, T.N.Z.I., xxxvii, 218, pi. 7, f. 1, 2. Not C. striata, 

 Hutt. : Pilsbry, Man. Conch. (1), xv, 319, pi. 59, f. 11, 12. 



Shell small, subcylindrical, truncated above and rounded at the 

 base, thin, white, axially sharply striate. Sculpture consisting of 

 somewhat inequidistant numerous flexuous sharp axial striae, much 

 narrower and sharper than in pygmcea ; there is no spiral sculpture. 

 Colour white. Spire sunken, top concave, with a deep and mode- 

 rately broad perforation, through which part of the earlier whorls can 

 be seen. The last whorl forming the height of the shell ; its first half 

 is almost straight at the middle, the second half distinctly contracted ; 

 narrowly rounded above, broadly convex at the base. Aperture as 

 high as the shell, narrow above, widened and slightly effuse below. 

 Outer lip thin and sharp, advancing and slightly concave at the middle, 

 convex above and below. Columella vertical, short, thickened, "ob- 

 liquely truncated below, slightly twisted, forming a more or less 

 distinct angle with the parietal wall, which is convex at its lower 

 part, straight above. Inner lip narrow, bounded by a fine ridge at 

 the columella, extending as a thin glaze over the parietal wall. 



