234 Dr. J. Gwyu Jefireys on 



I regard S. osjjcra of Philippi as a variety of tlic present 

 species. The height of the sjnre is an nnrcUable character. 



Scissin-eUa tenuis *, Jcffr. 



Shell forming a depressed cone with an expanded base, 

 sloping to the pcriplicry and slit, very thin, scarcely semi- 

 transparent, and rather glossy : scuJj/fure, extremely nume- 

 rous and fine curved longitudinal striic, and equally numerous 

 and fine concentric or spiral stria?, which by their intersection 

 cause a regular but minute cancelh\tion ; the concentric striae 

 at the base are stronger and more distinct than the longitudi- 

 nal striffi ; the sculpture is of course interrupted by the peri- 

 pheral slit and groove : colour pearl-white : sjyire greatly 

 depressed : ichorls 5, somewhat flattened below the suture ; 

 the last enormously exceeds in size all the others put together: 

 slit central, long and broad : groove also broad, marked across 

 by regular but rather distant curved stride ; edges sharp and 

 upturned : mouth obliquely oval : outer lip thin : inner lip 

 folded back and curved : pillar nearly straight, having a 

 twisted fold in front of the umbilicus, which is small and 

 narrow. L. 0-25. B. 0-2. 



Station 12, 1450 fms. ; two dead and imjierfect specimens. 



This differs from S. crispata and its varieties in its depressed 

 shape, thinner texture, more delicate sculpture, the larger size 

 of the last whorl in comparison with the others, the pillar 

 being furnished with a fold, and in its narrower umbilicus. 



Trochidae. 

 -Cyclostrema hasistriatum f, Jeffr. 



Shell somewhat globular, resembling in shape a small 

 Trochus of the Margarita section, thin, semitransparent, and 

 glossy : sculpture, more or less numerous and fine spiral striae, 

 which cover different parts of the surface in different speci- 

 mens ; sometimes they occur on the base only and encircle 

 the umbilicus, being in that case stronger ; at other times the 

 upper Avhorls have a single ridge-like stria at the top, so as 

 to give an augulatcd appearance to the crown or summit ; in 

 the young the umbilicus is suiTounded by a strong keel-like 

 stria : colour whitish : spire raised : ichorls 4, swollen ; the 

 last occupies three fourths of the spire ; the first or topmost 

 whorl is rounded and blunt : suture deep : mouth circular, 

 slightly angular above : umhilicxis rather naiTOw, but deep : 



* Thin. t Striated at the base. 



