88 BULLETIN 90, UNITED STATES NATIONAL MUSEUM. 



stone of Jacksonboro, Georgia, which was sent to me as Claibornian 

 by the late Professor Whitfield has since been proved by Dr. T. 

 Wayland Vaughan, of the United States Geological Survey, to be 

 Oligocene in age. 



STROMBUS LIOCYCLUS. new species. 

 PL^te 13, figs. G, 7. 



Shell small for the genus, slender, with a rather narrowly attenu- 

 ated spire, and 7 (or more) w^horls; apex decollate in the specimen, 

 having originally about two or three more turns than are pre- 

 served; whorls moderately convex and slightly shouldered; whole 

 surface originally sculptured with minute, close-set, straight, axial 

 threads; on the fourth whorl, counting backward from the aperture 

 there are about IG rounded riblets, which become obsolete toward 

 the sutures and pass insensibly into the somewhate narrower inter- 

 spaces; on the apical whorls, as in most species of this group of 

 the genus, these riblets are narrower, closer and less prominent ; and 

 on the last half of the last whorl obsolete, there being about 7 on 

 this whorl, mostly on the first half of it, the series in the type-speci- 

 men on this whorl being confined to the shoulder of the whorl; the 

 upper whorls also show traces of faint, equal, revolving threads, 

 three behind and six in front of the shoulder on the penultimate 

 whorl; on the base of the last whorl there are also traces of half a 

 dozen shallow rather distant spiral grooves, though the canal proper 

 seems smooth; aperture narroAV, produced and patulous behind; 

 the outer lip straight, thickened, parallel with the inner lip, in- 

 ternally without lirae; ocular sulcus shallow, wide; canal short, 

 wide, slight!}^ recurved ; inner lip smooth, somewhat callous. Length 

 of shell 36.5, of last whorl 27.5, of aperture 24.5, maximum diameter 

 17.5 mm, 



Tampa silex beds at Ballast Point, Tampa Bay, Florida. One 

 specimen from the Post collection, U. S. Nat. Mus. No. 165101. 



Superfamily CERITHIACEA. 



Family CERITHIIDAE. 

 Genus BITTIUM Leach. 



Bittium (Leach MS.) Gray, Proc. Zool. Soc, Loudon, 1847, p. 154, No. 234. 

 Sole example, Murex reticulatus Montagu. 



BITTIUM PRISCUM Dall. 



Plate 8, fig. 3. 



Bittium (Sti/Uferina?) prisciim Dall, Trans. Wagner Inst., vol. 3, pt. 1, 

 p. 189, 1890; pt. 2, p. 275, pi. 11, fig. 6, 1892. 



Tampa silex beds at Ballast Point, Tampa Bay, Florida ; Shepard, 

 Dall, and Post. IT. S. Nat. Mus. No. 165103. 



