46 TRANSACTIONS OF THE WAGNER FREE 



nucleus of one whorl ; outer lip arcuate, simple, sharp ; inner lip with a mod- 

 erate callus, hardly lirate ; pillar straight, slightly twisted, with a groove behind 

 it ; canal short, wide, shallow ; siphonal fasciole distinct, bordered behind by 

 a faint sulcus, behind which again is a still fainter indication of a depressed 

 line. Max. Ion. of shell 9.25 ; max. lat. 5.25 mm. 



Ballast Point silex-beds ; Dall, Shepard. 



It is not unlikely that, when fully adult, this shell has the pillar lip lirate ; 

 but even if it is immature it cannot be united with any of our Tertiary species. 

 It is perhaps nearest some of the recent forms like 0. strigata Reeve and 0. 

 ftiscocincta Dall from the West Indies, none of which, however, are as broad 

 and thin as 0. lata. 



Genus ANCILLARIA Lamarck. 



Ancillaria Shepardi n. s. 



Plate 4, figure 4. 



Shell slender, acutely pointed, with its surface on the spire glazed with a 

 coating of enamel, but indicating about five whorls ; aperture less than half the 

 length of the shell, callous at the posterior commissure and on the body ; outer 

 lip arched, simple, thin, perhaps with a slight projection in the adult, near the 

 canal, between the two principal sulci of the whorl ; canal wide and deep ; 

 pillar concave and twisted, scored with numerous fine shallow, spiral grooves, 

 and with a pronounced sulcus behind it ; the anterior end of the pillar is 

 obliquely truncate, shorter than the aperture and with its anterior edge exca- 

 vated so as to make a shallow gutter, behind which the edge of the whorl 

 projects in a rounded point before falling to the siphonal notch. In this man- 

 ner, when looked at directly from in front, the shell seems to have two canals, 

 one small and shallow, curving with the pillar, the other larger and deeper, cut 

 out of the wall of the whorl. On the base behind the pillar is the usual sulcus, 

 followed by the siphonal fasciole bordered behind by a sharp impressed line ; 

 then follows a band about as wide as the siphonal fasciole, but of which the 

 anterior half is convex and the posterior half impressed; this is bordered by 

 a band or fasciole between two sharply and deeply incised lines ; this fasciole is 

 transversely striate with backwardly somewhat concave lines and corresponds 

 to the tooth or projection of the outer lip, if one existed, which is not certain. 

 On the last whorl in front of the suture is another impressed spiral line or 

 groove, not very distinct on the fossils, but which seems to have formed the 

 anterior border of the enamel on the spire; the callus on the inner lip does not 

 thin out over the body, but is bounded by a straight line extending from the 

 columellar sulcus to the spiral line just described; the posterior commissure 

 of the aperture is-Tnore or less filled with callus. Max. Ion. of shell 34.75; 

 of aperture 17.0; max. lat. of shell 14.5 mm. 



Silex-beds of Ballast Point and the shores of Hillsboro' Bay, Tampa Bay, 

 Florida ; Shepard, Newman and Dall. 



