1899.] NATURAL SCIENCES OF PHILADELPHIA. 371 



■Compare *S'. obeliscus (Mor. ) with X. calcareus (Born), or *S'. 

 (figas (Poey) with N. cuneus (Pfr. ). 



Genus CALLIONEPION iiov. 



Shell turreted, slowly tapering, with diamond-granulate uepionie 

 shell of about 2h whorls, retained in the adult, the subsequent 

 whorls differently sculptured. Type species with 9^ moderately 

 •convex whorls, apex very obtuse. Aperture ovate, with slightly 

 expanded outer lip, the columellar lip with free expanded edge (as 

 in Bulimulus or Opeas) ; columella with a small, rather sharp 

 oblique median fold. 



Genitalia (PI. XV, fig. 8) without accessory organs; atrium 

 short. ^ system with the penis large, elongate, the vas defei'ens 

 inserted at its apex, beyond which a hollow tube or sack (fig. 8, x. ) 

 of unknown nature extends, terminating in a short retractor mus- 

 cle; talon (t.) large, composed of a thick curved basal portion and 

 a slightly longer, narrow terminal part. $ system with the vagina 

 short; spermatheca globular, lodged near the heart, its duct long 

 and slender; free oviduct very short, the convoluted portion un- 

 usually long ; albumen gland well developed. Hermaphrodite duct 

 moderately convoluted. 



Apparently oviparous, the young shell when hatched about one- 

 tenth the length and less than one-third the diameter of the adult 

 shell. 



The right eye-retractor muscle passes between c? and $ branches 

 of genital system; the penis retractor muscle is inserted upon the 

 diaphragm. 



The jaw is lost, and the radula obtained is frayed at the 

 edges, so that the number of teeth in a transverse row cannot be 

 stated, but it was probably not over fifty. The rachis consists of 

 well-developed teeth, fully as v/ide as the laterals, with square basal 

 plate and tricuspid reflection, the middle cusp large, though shorter 

 than the basal plate ; the side cusps small. In the lateral teeth an 

 inner cusp is absent. Marginals similar, with oblique mesocone, 

 acute small ectocone and short basal plate. 



Type CaUionepion Iheringi n. sp. 



Affinities of CaUionepion. 

 The peculiar disparity between the sculpture of the nepionic and 

 post-uepionic whorls of the shell (when not obscured by erosion), 



