98 CYCLOSTREMA. 



C. PROxiMA, Tryon. PL 33, fig. 4. 



Narrowly umbilicated, faintly striate, with a few indistinct spiral 

 lines below tlie sutnre, and numerous well defined ones on the base, 

 around the umbilicus the inferior strife stronger, surface smooth, 

 greyish white, suture impressed, whorls very convex, rapidly in- 

 creasing; periphery round, thin, slightly in contact. 



Diam. 2-2 mill. Off New England Coast; S-iZ fms. 



Said to be closely allied to C basistriata, Brugnone. Described 

 by Prof. Verrill as C. afflnis, preoccuj)ied by Jeffreys for the pre- 

 ceding species. 



C. TENERA, Jeffreys. PI. 33, fig. 6. 



Narrowly umbilicated, thin, semitransparent, lustreless, with 

 nearly microscopic spiral stride, which are wanting on the base and 

 replaced by a rugose or fretted appearance, pale yellowish white, 

 with a faint greenish tinge, suture very deep; whorls 4, convex; 

 mouth circular, peristome thin, slightly expanded. Diam. 2*5 mill. 



European Atlantic (Porcupine Exped.) 



C. siMiLis, Jeffreys. PI. 33, fig. 7. 



Moderately umbilicated, depressed turbinate, rather thin, glossy, 

 opaque, without sculpture; whorls 42, convex, rapidly increasing, 

 suture wide and deep; mouth nearly circular, slightly appressed, 

 peristome thin. Diam. 1"25 mill. 



European Atlantic (Porcupine Exped.) 



C. Valvatoides, Jeffreys. PI. 33, fig. 8. 



Narrowly umbilicated, rather solid, opaque, glossy, with a few' 

 irregular growth-lines, yellowish white, spire with rather flattened 

 apex, suture deep ; whorls 4, well-rounded ; peristome considerably 

 expanded. Diam. 3'12 mill. 



European Atlantic (Porcupine Exped.) 



C. sph^roides, S. Wood. PI. 32, fig. 69. 



Narrowly umbilicated, white, spirally costate; whorls three, rapidly 

 increasing, suture deep. Diam. 1*25 mill. 



Bay of Biscay^ 



Described as a fossil of the Crag, Sutton, England, and said to 

 be nacreous in the original diagnosis. 



