INSTITUTE OF SCIENCE, PHILADELPHIA. 379 



upper end of the umbilicus by an extension of the body-callus. All De 

 Gregorio's figures of " 6". striata Lea," except figure 9, plate 15, represent 

 5'. declivis. We have it also from Wood's Blufif, Ala. 



Sigaretus arctatus Conrad, a small, depressed species, with a thin edge to 

 the pillar, only reflected near the upper end, is known from Claiborne and 

 Vicksburg, Miss. 



5. inconstans Meyer and Aldrich is another small, depressed species, with 

 the ioxxxvoi Haliotis asinina. It is known from Claiborne and Newton, Miss., 

 and the vicinity of Darlington, S. Car. 



In the Miocene, beside those about to be more fully referred to, we have 

 S.fragilis Conrad (+ apertus H. C. Lea), from the Chesapeake Miocene of 

 Maryland and Virginia ; and -S. multilineatns Gabb, from the Miocene of Costa 

 Rica. 5. nnmismalis Gabb, from the same horizon, may prove to be a broken 

 Neverita. S. perspectivus Say, well known as a recent shell, as a fossil does 

 not appear to antedate the Post-Pliocene. 



Sigaretus chipolanus n. s. 

 Plate 17, figure 7. 



Older Miocene of the Chipola beds, Calhoun Co., Florida, Burns ; and of 

 the Orthaulax bed at Ballast Point, Tampa Bay, Dall. 



Shell solid, rather thick, varying in rotundity with age, the young ones 

 as a rule being more naticoid in shape, while the more advanced are relatively 

 flatter, and the fully mature specimens again are more rotund; whorls four or 

 five, sculptured with rather fine, flattish, revolving threads of varying size, sepa- 

 rated by channelled interspaces, varying in width and minutely undulated or 

 reticulated by the sharp, close-set, fine incremental lines ; aperture large, ob- 

 lique ; base somewhat flattened, periphery rounded; pillar- lip arched, broad, 

 flattened somewhat and sometimes excavated, with a narrow sulcus behind it, 

 running up to the imperforate umbilical region ; callus on the body moderate, 

 lip not reflected. Max. Ion. of adult 33 ; diam. 27 mm.; Ion. of young shell 

 16.5 ; axial elevation 11 ; diam. 15 mm. 



This species is most nearly related to J?, declivis, from which it may be 

 separated by its closed umbilicus and the absence of the emargination of the 

 pillar, which is the most characteristic feature of rf?<r/K'W. It also recalls S. bilix 

 var. mississippiensis, which has a perforate umbilicus and is more rotund. The 

 specimen figured is from the silex-beds ; the much larger and more char- 

 acteristic specimens from Chipola were only obtained later. The sculpture 

 may be close or sparse ; it varies in this respect in nearly all the species. 



Sigaretus multiplicatus n. s. 

 Plate 20, figures 12, 12 b. 

 Pliocene of the Waccamaw River, S. Carolina, Johnson, and of the 

 Caloosahatchie beds, Florida ; Willcox. 



