34 PROCEEDINGS OF THE ACADEMY OF [Feb., 



visible in some of the intervals. The last whorl is convex, having 

 ribs like those of the spire on the front, none on the back, but two 

 precede the small, smooth lip-varix. The intercostal intervals are 

 marked with deeply impressed spiral grooves, obsolete on the crests 

 of the ribs on the front, and on the smooth dorsal patch, but passing 

 over the ribs behind the lip. The outer lip has a heavy callus within, 

 bearing about 9 teeth, the upper ones stronger. The columella 

 bears a series of 8 teeth. The columellar edge is slightly raised, and 

 there is a very heavy callus upon the body at the posterior commissure 

 of the aperture. 



Length 10.5, diam. 5.7 mm.; length of aperture 6 mm. 



Solenosteira dalli Brown and Pilsbry. 

 Murex gatunensis Brown and Pilsbry. 

 Murex pomum Cimelin. 

 Typhis linguiferus Dall. 



Typhis linguiferus Dall, Trans. Wagner Inst., Ill, pt. 1, p. 152, PI. 12, fig. 7. 



The single specimen agrees well with the description and figure of 

 Ball's Chipola species, except that the spines on the varices are 

 erect instead of curved. 



Cassis monilifera Guppy. 

 Polinices mammillaris (Lam.). 

 Potamides avus n. sp. PI. 5, fig. 5. 



A species closely related to P. pacificus Sowerby, but differing by 

 the different shape of the last whorl. The coronal tubercles are 

 situated higher, directed somewhat upward, and there is no hump 

 on the base in front of the aperture. The surface is strongly striate 

 spirally. The inner lip has a distinct callous ridge near the posterior 

 commissure of the aperture. There are about ten of the pointed 

 tubercles on the last whorl. 



This appears to be an ancestor of the recent species, which has 

 more exaggerated sculpture. 



Turritella cartagenensis n. sp. PI. 5, fig. 13. 



The whorls are nearly flat, but there is a slight concavity in the 

 upper half and they are a little prominent below the suture; the 

 periphery has a rounded prominence, visible above the suture. The 

 light lines of growth are strongly retractive from the upper edge to 

 below the middle of the visible surface of each whorl, then curving 

 and becoming vertical or slightly protractive in the rest of their 

 course. Spiral sculpture of unequal, unevenly spaced threads of 

 various sizes, distinct but in low relief. There is^a noticeable cingulus 



