96 TRANSACTIONS OF THE WAGNER FREE 



behind, wider in front ; outer lip simple, inner lip hardly glazed ; pillar straight, 

 with two small, oblique pustules about the middle, the posterior the larger of 

 the two. Lon. of shell 4.0; max. lat. 1.5 mm. 



This minute and very pretty species was found by me in the Caloosahatchie 

 marl. Only two specimens were found. It appears quite distinct from any 

 described species. When fully adult this and the preceding species, like 

 the recent ones, probably have the outer lip a little thickened and even mi- 

 nutely denticulated on its inner edges. Even in the recent species it is rare to 

 find specimens having full marks of maturity, so it is not safe to infer from their 

 absence in a few specimens that they are always absent. 



Family TURBINELLIDvE. 

 Genus TURBINELLA Lamarck. 



The earliest species yet recorded, though doubtless not the earliest to ap- 

 pear in the New World, is Tiirbinella Wilsoni of Conrad, from the Vicksburg 

 or Upper Eocene horizon of Mississippi. This species was marked by a small 

 nucleus and many-whorled, acute spire. In the Lower Miocene appeared T. 

 polygonata Heilprin and 7! c/«/i7/rt«« Dall, before T. H^27.yo«?' became entirely 

 extinct. T. chipolana, which is found in the same bed (Alum Bluff, lower 

 horizon) with the last specimens of T. VVilsoiii, is distinguished from it by its 

 shorter spire, more inflated whorls and singular long, cylindrical nucleus, 

 recalling that of Volutopupa. Higher up in the Pliocene marls this form is 

 succeeded by the large T. regma and T. scolymoides, whose somewhat degener- 

 ate recent descendants are the T. ovoidea and T. scolymus of the West Indies. 

 7. Wilsoni is of moderate size, T. polygonata large, T. chipolana moderate, T. 

 scolymoides larger than T. scolyimis. 



In the subgenus Vasum we begin with the V. siibcapitelliim Heilprin and 

 the V. engonatum Dall of the Lower Miocene, both of which types persist, 

 though modified, to the present time, while in the Pliocene the elegant V. 

 horridiim Heilprin made a brief sojourn and is not represented in any recent 

 form. 



Turbinella Wilsoni Conrad. 

 Tiirbinella sp. Lesueur, Walnut Hills Fossil Shells, pi. 3, fig. 14, 1829. 

 Turbinella IVilsoni Conrad, Journ. Acad. Nat. Sci. Piiila. ii. vol. i,p. 120, pi. 12, fig.12, 1S48 



(Vicksburg). 

 Mazza Wilsoni Conrad, Cat. Eocene Foss. A. J. C. i. p. 23, 1865. 



Vicksburg group, Upper Eocene, Vicksburg, Miss. ; Lower Miocene at 

 Alum Bluff (lower bed), West Florida; F. Burns. 



The characteristics of this form are its somewhat flattened or subcylindri- 

 cal last whorl, a constriction near the suture, which in the earlier whorls in- 

 duces a presutural rounded band ; a rather steep slope from the appressed 

 suture to the obscurely nodulous shoulder; five or six rounded, distant, strong 

 transverse ribs in front of the sutural band in the early whorls ; a very acute. 



