370 PROCEEDIlsrGS OF THE ACADEMY OF [PaRT II 



Length 50, diam 18.5 mm. (Type). 



It seems to have reached a length of about 60 mm. or more. Re- 

 sembles somewhat the figure of C. caloosaense var. heilprini Dall, 

 of the Floridian Pliocene. 



Type and nine other specimens no. 2597 A. N. S. P. 



Cerithium turriculum Gabb. Plate XXXIII, flgs. 1, 2, 8.. 



C. turriculum Gabb, Tr. Am. Philos. Soc, xv, 1873, p. 238. 



Sculpture of strong axial folds, angular at the shoulder, on the 

 median whorls; earlier whorls have lower folds, not angular, and 

 the last whorl has very short folds next the suture. Spiral striation 

 of unequal threads. The broken type specimen figured is 24 mm. 

 long, and has twelve folds on the last whorl. 



The sculpture varies a good deal among the 23 examples. 



This is probably an ancestral form of the more robust C. moenensis 

 Gabb, from the Pliocene of Costa Rica. 



Type no. 4067; 22 other specimens no. 4068 A. N. S. P. 



Cerithium dominicense Gabb. Plate XXXIII, flgs. 3, 4. 



Cerithium dominicense Gabb, Tr. Amer. Philos. Soc, xv, 1873. p. 328. 



The last 2| whorls have prominent rounded tubercles below the 

 suture, about 9 on a whorl. Below these there are about 6 tuber- 

 culiferous cords on the last whorl, with finer, unequal threads in 

 their intervals. The earlier whorls have axial folds crossed by 4 or 

 5 principal spiral cords; at first every third fold is somewhat larger, 

 then every fourth ; but on the last three whorls such variceal folds 

 do not appear. None of the specimens has a perfect aperture. 



Length 25.7, diam. about 11 mm. 



Type and three other specimens no. 2594 A. N. S P. 



Cerithium uniseriale Sowerby. Plate XXXIII, flgs. 16, 20. 



Cerithium uniseriale Sowerby, Q. J. Geol. Soc, vi, 1849, p. 51. Not of Guppy. 



One specimen, broken at the aperture, has the characters called 

 for by Sowerby 's diagnosis. It is related to C. ohesum Gabb, but 

 there is a band of low tubercles below the suture, separated from the 

 principal series by a depression, and the spiral striation is coarser, 

 uneven, with some weakly granose spirals. 



We beheve that Gabb's identification of this species is correct. 

 Guppy 's interpretation (Q. J. Geol. Soc, xxxii, pi. 29, fig. 4) is 

 not in accord with Sowerby 's diagnosis. It is C. ohesum ventricos- 

 ior. C. ohesum of Guppy, tab. cit. f. 9, may be a young C. simplex 

 Gabb, though this is not certain. 



