﻿Notes on the Tertiary of Alabama and Mississippi. 



151 



This fine species closely resembles the figure of T. humerosa 

 Con., from Piscataway, Md. , but on a direct comparison with 

 specimens from the typical locality proves to be quite distinct. 



Cerithium Langdoni, n. sp., PI. 3., fig. 14. Shell subulate; 

 whorls 13 to I5(?); surface cancellated ; suture indented ; about five 

 prominent revolving lines on each whorl ; whorls compressed 

 suddenly at both sides of the suture ; longitudinal ribs numerous, 

 prominent, wavy, continuing over the impressed spaces and ter- 

 minating at the suture ; revolving line next below the suture split- 

 ting into two on the lower whorls ; body whorl carinated ; mouth 

 nearly round ; canal recurved, short, rather close. Length of that 

 part of the shell remaining, -f^ of an inch. 



Locality, Red Bluff, Miss. 



The aperture in the specimens on hand is not entire, and several 

 whorls are missing from the spire. A very distinct species ap- 

 proaching C. nassula Con. The peculiar indentations around the 

 suture give the shell a screw-shaped appearance. 



Named in honor of D. W. Langdon, Jr., Assistant on the Ala- 

 bama State Geological Survey. 



Triforis Americanus, n. sp. PI. 3, fig. 16. Shell, sinistral, small, 

 conical ; whorls, nine, striate, covered with revolving beadlike lines ; 

 suture, distinct, shell compressed just above the suture, with two 

 lines thereon, a broad, prominent beaded line encircling the whorls 

 just above the center, itself divided in some specimens by an im- 

 pressed line ; apex, smooth, mammillated; shell, slightly shouldered 

 at the suture, it being bordered by an impressed line , body whorl 

 convex, lines of growth giving it a cancellated appearance ; canal 

 twisted, one-third length of aperture, not quite closed ; mouth, ob- 

 long-ovate, about one-fourth the length of the shell ; outer lip, 

 sharp, plicate within. 



Locality, Jackson, Miss. 



This is, I believe, the first species of the genus described from 

 the older Tertiary of the Southern States. It is an exceedingly 

 pretty shell. 



