476 PROCEEDINGS OF THE ACADEMY OF [1898. 



and undoubted distinctness, so far as specific distinctions can be 

 said to exist in Cerion, we present them as a further contribution 

 to knowledge of this peculiar genus. 



Since writing upon this topic in 1896, we have been unable to 

 procure living or suitably preserved specimens of Cerion for anatom- 

 ical investigation ; but we have no reason to doubt that such study, 

 when it becomes possible, will justify our reference of the genus to 

 the family Urocoptidce (" Cylindrellidce" of authors). 



Respecting the extraordinary plasticity of the shell under the 

 force of varying circumstan.ee, something was said in our former 

 communication ; but as it would seem from questions put to us by 

 various conchological friends, the case was not stated strongly 

 enough. We do not seek paradox when we say that frequently the 

 differences between individuals of a species are greater than the 

 differences between species ; so wide is the swing of racial and in- 

 dividual variation. 



Cerion torrei Blanes. Figs. 1, 2. 



Shell cylindrical, obese, strong, rimate and perforate, the lower 

 two or three whorls of approximately equal diameter, those above 

 forming a rather short cone with sides diverging at an angle of 85° 

 to 90°. Whorls 10-11, the earliest 1-2 J white or corneous, several 

 following finely and sharply striated, the remaining whorls nearly 

 smooth ; last whorl ascending in front, somewhat tapering below, 

 and generally striated at the base. Brown, marbled with very irre- 

 gular stripes and dots of white. Aperture short, showing a small 

 short parietal tooth and a small columellar fold ; peristome white, 

 thickened and convex, reflexed and recurved, continuous, the 

 parietal margin more or less calloused. 



Alt. 23j, greatest diam. 13, length of aperture 11 mm. 



Alt. 28, greatest diam. 124, length of aperture 11 mm. 



Alt. 24, greatest diam. 11 2, length of aperture 10 mm. 



Port of Vita, Cuba (Francisco E. Blanes). 



This species resembles C. dimidiatum, differing in being of less 

 rude texture, less squarely obese form, higher terminal cone, no trace 

 of a keel defining the base, etc. 



It has the coloration of C. vulneratum. 



Var. omatum P. & V. Figs. 3, 4. 



Similar in form to the longer specimens of C- torrei, but strongly 

 and regularly ribbed throughout, the ribs on the cylindrical portion 





