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and are nearly entirely rose-coloured, the nucleus and a few spots below the suture are white; in 

 the largest specimen the last whorl is blackish with rose-coloured, spiral lines. The upper whorls are 

 spirally striated, base with a few striae. Though this species has more the shape of a Stoinatella 

 than of Gena, the smooth, shining, last whorl agrees with its location in the genus Gena. 



Miraconcha Bergh. 

 1. MiraconcJia obscura Bergh. 

 (See Appendix). 



Fam. SCISSURELLIDAE. 

 Scissurella Orbigny. 



1. Scissurella maxima n. sp. PI. VI, fig. 9. 



Stat. 17S. 2°4o'S., I28°37'.5E. 835 M. Blue mud. 2 Spec. 



Shell large, thin, depressed, yellowish-white; whorls about 4^3, convex above, concave 

 towards the slit, rapidly increasing; nucleus smooth, sculpture consisting of numerous fine, curved, 

 radiating ribs, interrupted on the lower whorls by the slit-fasciole, these ribs are crossed by 

 spiral lirae of which there are about 10 on the upper surface, besides a few secondary ones, 

 they form small square beads when they cross each other; the sculpture of the base is similar, 

 with the ribs more crowded towards the aperture; slit long, peripheral, rather wide, deep, with 

 upturned edges, striated by arched, lamellose striae. Umbilicus partly covered by the columellar 

 margin. Aperture rounded, very oblique, angular at the insertion on the body-whorl and at the 

 periphery, outer and basal margin rounded, thin, columellar margin slightly concave, a little 

 reflected at the upper part, stronger so below, where it joins the basal margin ; on the body 

 whorl the margins are connected by a thin layer of enamel. 



Alt. 4^3, diam. maj. 6^3; apert. alt. 3, lat. 3 Mill. 



This species may be distinguished by its shell, which is large for the genus, in shape 

 but not in sculpture, it resembles Sc. U77ibilicata Jeffr. 



2. Scissurella exquisita n. sp. PL VI, fig. 10. 



Stat. 95. 5°43'.5 N., ii9°4o'E. 522 M. Stony bottom, i Spec. 



Shell rather large, very thin, transparent, white, depressed, whorls about 373, convex 

 above, concave towards the slit, rapidly increasing; nucleus rather smooth, sculpture of the upper 

 whorl consisting of very numerous, radiating, elevated striae, which are curved and crossed from 

 about halfway the penultimate whorl by weaker spiral ones, about 1 5 on the upper part of last 

 whorl, sculpture of the base similar, slit-fasciole a litde above the sutures, rather wide, with 

 upturned edges, striated across by arched striae, slit 3Y3 Mill. Umbilicus narrow, partly covered 



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