232 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.46. 



ing the ribs about in the middle. Length of 8 whorls, 10; maximum 

 diameter of last visible whorl, 2.5 mm. 



Station 6440, near Burkeville, Texas, Matson. Type, U. S. Nat. 

 Mus., No. 166316. 



The base of the last whorl is missing in both molds. The sculpture 

 recalls that of Terebra, but the general aspect is more like CeritJiiopsis. 

 The description is drawn from a gutta-percha cast from the original 

 mold. 



PACHYCHEILUS ANAGRAMMATUS, new species. 



Plate 21, figs. 5,8. 



Shell slender, with about 11 whorls, the earlier ones smooth, 

 rather flat-sided, but with a distinct suture; the later ones more 

 rounded, with spiral cords, at first obscure, later sharp, with wider 

 channeled interspaces, about 4 between the suture and the periphery; 

 on the base about 6, the outer cord distinct, the others becoming more 

 feeble and obscure toward the axis; or the whole shell may be smooth 

 and flat-sided like the early whorls; aperture rounded, the peritreme 

 sharp, simple, a rather thick callus spread over the body. Length 

 of shell when complete, about 24; diameter of last whorl, 8 mm. 



Stations 6040, Louisiana, and 6440, Texas; Matson. Type, U. S. 

 Nat. Mus., No. 166295. 



PACHYCHEILUS CANCELLOIDES Aldrich. 



Potamides cancelloides Aldrich, Nautilus, vol. 24, pt. 12, p. 138, pi. 8, figs. 2, 2a, 

 1911. 



Station 6132, Aldrich and Matson, Satilla River, Georgia. 



This species appears to belong rather to PachycJieilus than to 

 Potamides. 



PACHYCHEILUS SATILLENSIS Aldrich. 



Potamides saltillensis Aldrich, Nautilus, vol. 24, pt. 11, p. 132, pi. 8, figs. 1, la-c, 

 1911. 

 Station 6132, Aldrich and Matson. Also at station 6440, near 

 Burkeville, Texas, Matson. ^ 



PACHYCHEILUS SUA VIS, new species. 

 Plate 21, figs. 6, 9. 



Shell acutely conical, with about 10 whorls, the apical portion 

 sculptured, the last 2 whorls smooth, except for incremental lines; 

 nucleus very small (not seen); subsequent whorls (except the last 

 one or two) with about a dozen flexuous ribs with wider interspaces, 

 crossed by 4 or 5 flattened spiral cords separated by narrow grooves ; 

 this sculpture is sometimes prolonged even to the last whorl, becoming 

 gradually feebler, yet in the majority of cases it becomes obsolete on 

 the eighth and is wholly absent on the last whorl. The latter is 



