INSTITUTE OF SCIENCE, PHILADELPHIA. 365 



vanished. The very large series in the National Collection shows this dis- 

 tinctly. Conrad, in Morton's Synopsis, confounds N. gibbosa Lea, which is a 

 Neverita, with N. semilunata, and refers them both to his (or Say and Mor- 

 ton's) N. (Btites, and subsequently restores both to specific rank (Am. Journ. 

 Conch, i. p. 27, 1865); but the species named in Say and Morton's leaflet 

 were not recognizably described, and in sixty years have not been figured, so 

 that we may properly ignore them, so far as they conflict with Lea's figures 

 and diagnoses. N. semihinata is known from the Claiborne sands and Lee 

 County, Texas. The operculum seems to be unknown. 



It has been referred, as I think incorrectly, to N. epiglottina Lam. by De 

 Gregorio, who figures quite a different species under the name of semihinata. 

 He regards the problematical N. cetites Conrad as a synonym, following 

 Bronn. He also figures a vzYXcty oi semihinata under the name oi AL Matlier- 

 oni Desh. 



Another species of the Eocene belonging in this vicinity is N. permunda 

 Conrad (Proc. Acad. Nat. Sci. 1855, p. 260 ; Wailes, Geol. Miss., pi. 16, fig. 2)^ 

 which is readily separated from N. canrena by the absence of the radiating 

 sulci on the spire. It is found in the Prairie Creek beds, Wilcox County, 

 Alabama, and in the upper Eocene of Ucutta Creek, Garland's Creek, and 

 Jackson, Miss. An apparently direct descendant of N. permunda is found in 

 the following species : 



Natica alticallosa n. s. 

 Plate 22, figure 28. 



Older Miocene of the Chipola beds at Ten-Mile Creek and on the 

 Chipola River, one mile from Bailey's Ferry, and in the lower bed at Alum 

 Bluff, Calhoun County, Florida. 



Shell resembling N. permunda Conrad, but smaller, and best described 

 by a differential diagnosis. 



Shell of four well-rounded whorls, with the suture well marked and the 

 surface smooth, except for lines of growth which are sometimes slightly ele- 

 vated near the suture ; male with the suture less impressed and the spire more 

 evenly sloping than in the other sex ; spire slightly less elevated than in 

 N. permunda ; aperture with a thick body-callus continuous with the umbili- 

 cal callus; the latter in N. permunda is coiled on the middle of the umbilical 

 wall, with a space between it and the antecedent whorl ; in N. alticallosa the 

 callus fills the upper two-thirds of the umbilicus completely, and sometimes 

 nearly reaches the umbilical carina, which last is less sharply defined than in 

 N. permunda, and consequently the aperture at the base of the pillar is some- 

 what less angular and effuse than in that species. Alt. of shell 18 ; max. 

 diam. 18 mm. 



The subsutural callus in this species is generally separated from the outer 

 lip at the body by an obscure groove, and the callus here projects forward on 

 the body beyond the lip. The operculum is unknown. 



