90 GASTROPODA. [Aspidobranchia. 



1. Schismope Atkinson!, Tenison-Woods, 1877. Plate 6, fig. 12. 



Scissurella Atkinsoni, T.-Woods, P.R.S. Ta,s., 1876 (1877), 149. Schismope 

 Atkinsoni, T.-Woods, P.R.S. Tas., 1877 (1878), 43 ; Man. Conch. (1), 

 xii, 66; Pritchard and Gatliff, P.R.S. Vic. (n.s.), xv, 181. S. carinata, 

 Watson, Chall. Rep., xv, 1886, 119, pi. 8, f. 6; Man. Conch. (1), xii, 

 65, pi. 65, f. 17-19. S. Atkinsoni, T. - Woods : Suter, T.N.Z.I., 

 xxxix, 268. 



Shell small, tumid, but depressed, umbilicated, strongly keeled. 

 Sculpture : There are above and below sharp, distant, curved radiating 

 riblets, interspaces microscopically striate ; the spiral sculpture is 

 formed by a strong, rounded, double keel, formed by the two edges 

 of the canal-scar ; this canal is sunken, and strongly scored ; above 

 the canal a few microscopic spiral threads ; below there are on the base 

 3 strong threads, of which the highest is the strongest ; a still weaker 

 thread encircles the umbilicus. Colour hyaline, dead shells white. 

 Spire slightly exserted, whorls flat above, rising roundly from the 

 suture. Apex very small, tabulated. Whorls 4, rapidly increasing, 

 strongly keeled by the canal-ridge, angulated by the highest thread ; 

 base very tumid. Suture rectangular. Aperture oval, very oblique. 

 Outer lip runs in straight lines and angles, slightly curved on the base. 

 Inner lip thin and short. Columella concave, often slightly reflexed. 

 Umbilicus large, shallow, defined by a keel. Anal perforation long and 

 narrow, rounded behind, drawn out into a long fine point in front, 

 without a projecting lip on the inner side. 



Diameter, 2-5 mm. ; height, 2-25 mm. (type). Diameter, 1-5 mm. ; 

 height, 1-25 mm. (" Challenger " specimen). Diameter, 2-6 mm. ; 

 height, 2 mm. (Bounty Island specimen). 



Type in the Tasmania n Museum, Hobart. 



Hab. Whangaroa Harbour ; Snares and Bounty Islands, in 

 50 fathoms (Captain Bollons). Australia and Tasmania. The type 

 is from Blackmail's Bay, Tasmania. 



2. Schismope Beddomei, Petterd, 1884. Plate 6, fig. 13. 



Schismope. Beddomei, Petterd, Journ. of Conch., iv. 1884, 139 ; Man. 

 Conch. (1), xii, 67 ; Tate and May, P.L.S. N.S.W., 1901, 407, pi. 24. f. 24 ; 

 Pritchard and Gatliff, P.R.S. Vic. (n.s.), xv, 181 ; Hedley, Rec. A.M., v, 

 1904, 89. 



Shell small, thin, turbinately depressed, umbilicate. The spiral 

 sculpture is formed by a strong keel of the raised edges of the canal- 

 scar ; above and below this keel the last whorl is distinctly concave 

 and smooth ; there are a few short radiate riblets spreading from the 

 suture on the upper side ; base with about 12 distant, sharp and strong, 

 oblique riblets. Colour white, dull. Spire low, tabulated. Whorls 

 3i, very rapidly increasing, flattened at the apex. Aperture ovate, 

 oblique, of moderate size. Outer lip sharp, broadly convex. Inner 

 lip spread a short distance over the body, and forming a sharp angle 

 with the outer lip. Columella concave truncated below, slightly 



