264 TRANSACTIONS OF THE WAGNER FREE 



forms of this species. The form and sculpture of the Pliocene specimens are 

 absolutely identical with those of the recent specimens and vary through the 

 same series of variations. If any difference can be detected, it is that on the 

 average the size of recent specimens may be a little larger than the average 

 of the fossils. 



Triforis perversa Linn4 var. modesta C. B. Adams. 

 Cerithium viodeslmn Adams, Contr. Conch., p. 117, April, 1850. 



Old Miocene of the Chipolabeds, Florida, Burns; Pliocene of the Caloo- 

 sahatchie beds on the Caloosahatchie River, Shell Creek and Alligator Creek 

 in Florida, Dall and Willcox ; living in the West Indies to Jamaica, Adams. 



This form is smaller than nigrocincta and uniformly dark-colored in life • 

 in the middle row the nodules are smaller than on the outer rows, the outline 

 is slightly inflated. The living specimens intergrade with the Southern form 

 of nigrocincta, and for that reason I regard it a Southern race or subspecies 

 of the nigrocincta-perversa stock. 



Triforis melanura C. B. Adams. 



Cerithium monitiferum H. C. Lea, Trans. Am. Phil. Soc, 2d Ser., vol. ix. p. 269, pi. 37, 



fig. 2, 1845 I "ot of Defrance. 

 Cerithium melanura C. B. Adams, Contr. Conch., p. 117, 1850. 

 Ceritliium subtnoniliferum Orbigny, Prodr. Pal. iii. p. 83, 1852. 

 Triphoris monitiferum Emmons, Geol. Rep. N. C, 269, fig. 169, 1858. 



Older Miocene of the Chipola beds, Florida; Newer Miocene of the 

 Chesapeake formation, Petersburg, Virginia, Lea, and N. Carolina, Emmons; 

 living from Cape Hatteras, N. Carolina, southward to the Antilles in shallow 

 water. 



This is very closely related to modesta, from which it differs in color, 

 when living, in being more cylindrical and slender, while the spiral rows of 

 nodules are not connected by any transverse ribbing, and are of a more even 

 size than in that form.' I have little doubt that it will be found in the Caloosa- 

 hatchie Pliocene when more thoroughly searched. 



Triforis distincta O. Meyer. 

 Triforis distinctus O. Meyer, Ala. Geol. Rep., p. 73, pi. i. figs. 5, 5 a, i886. 



Eocene of the Claiborne sands, Meyer ; Older Miocene of the Chipola 

 beds, N. W. Florida, Burns. 



Though both diagnosfs and figure are brief and unsatisfactory, there is 

 little doubt that the Chipola species is that described by Meyer. His type 

 is, however, a miserable, worn remnant of four whorls, wanting both apex and 

 body-whorl. The characters of the base described by Meyer are those of 

 immaturity ; all or nearly all the species have a flatfish base when young. As 

 the shell grows older the line visible at the suture in the early whorls disap- 

 pears under the margin of the subsequent whorl. The adult base has three 



