36 



and the shell bears strong ribs, becoming more distant as they approach the aperture, and being 

 obsolete on the last half whorl; these ribs have blunt spines, bordering the margin of the sub- 

 sutural excavation, and sharper ones at the periphery, which is keeled in the interstices of the 

 ribs. Last whorl with another keel at some distance from the periphery, with rather obsolete 

 indications of spines, corresponding to those of the upper keel, the space between the keels 

 and above the periphery somewhat concave. Umbilicus pervious, its margin strongly crenulated 

 or folded, the folds entering the umbilicus and partly running upwards, towards the lower 

 keel. Aperture circular, its inner lip protracted, outer lip very broad and thick, broadest at its 

 upper part, slightly excavated and reflected externally. The whole exterior of the shell covered 

 by low, crowded lamellae. 



iVlt. 4, diam. maj. 7^3, apert. alt. et lat. 2°/. Mill. 



Allied to Z. siderea Reeve, but more depressed if seen on the apertural side, the shape 

 differs by the more prominent peripheral keel, the outer lip is broader etc. 



Fam. Cyclostrematidae. 

 CyclOStrema Marryat. 



I. Cyclostrema reeveana Hinds. 



Hinds. Voy. of the Sulphur, p. 52, PL 16, fig. 17. 

 Reeve. Conch. Ic. Vol. I, Delphinula, fig. 17. 

 — ■ — Conch. Ic. Vol. XIX, Cyclostrema, fig. 13. 

 Adams. Proc. Zool. Soc. Lond. 1850, p. 42. 



Stat. 47. Bay of Bima, near south fort. 13 — 54 M. Mud with coralsand. I Spec. 



The only specimen though adult, is smaller than one from Cebu, having only a diameter 

 of 9 Mill., the sculpture however is the same; the body whorl has on its upper half three 

 principal keels, of which the uppermost forms an angle; on the flat space between this angle 

 and the suture, run three secondary keels or lirae; the lirae of the base, five in number, are 

 placed closer, the last one borders the umbilicus, or is partly placed into it. A short keel and 

 two fainter ones run in the umbilicus, these last rendering the external border of the columellar 

 margin crenulate. The radiating ribs, about fourty in number on the last whorl, form small 

 cusps, where they cross the lirae. Moreover the shell has in the interstices very fine growth- 

 striae, which become lamellose near the suture. The umbilicus has a lamellose appearance, by 

 the continuation of the ribs. 



Both Reeve and Adams cite Proc. Zool. Soc. Lond. 1843 for this species, but I cannot 

 find the description there. 



Teinostoma Adams. 

 I. Teinostoma sibogae n. sp. PI. II, fig. 5. 



Stat. 105. 6°8'N., 121° 19' E. 275 M. Coralbottom. i Spec. 

 Shell depressedly globose, imperforate, surface smooth, with scarcely visible lines of 



