388 TRANSACTIONS OF THE WAGNER FREE 



group in the Chipola Miocene. I prefer to wait for the reception of an adult 

 specimen before figuring the species. 



CoUonia claibornensis 11. s. 

 Plate 22, figure 26. 



Eocene of the Claiborne sands horizon, at Claiborne, Ala., Burns ; a 

 single example. 



Shell small, turbiniforni, spirally sculptured, of four whorls ; upper whorls 

 with small, alternated spirals, of which one larger than the rest partly tabulates 

 the whorls in front of the suture; periphery rounded, also the base, both 

 evenly spirally threaded, the interspaces obliquely cut by regularly spaced in- 

 cremental lines ; umbilicus closed, umbilical rib wide, strong, not very elevated ; 

 marginal sulcus at the pillar distinct, aperture rounded, margin thickened and 

 slightly expanded. Alt. 3.5 ; max. diam. 3.25 mm. 



The specimen had been broken before reaching maturity, which has 

 somewhat affected the growth of the umbilical rib. The umbilicus itself is 

 closed, but the form and character of the shell on the whole are so strikingly 

 similar to the younger stages of CoUonia elegantiila that I have little if any 

 doubt as to its generic place. 



Family TROCHID^. 



Genus CHLOROSTOMA Swainson. 



Subgenus Omphalius Pliilippi. 



Chlorosioma Swainson, Malac, p. 350, 1S40 (in part). 

 MoniUa and Liotrochus sp. Conrad, Proc. Acad. Nat. Sci. 1862, p. 569. 

 Monodonta sp. Tuomey and Holmes, Pleioc. Fos. S. C, p. 116, 1856. 

 Tiirbo sp. Heilprin, Trans. Wagner Inst. i. p. 113, 1S87. 



Though some of the American species of this group approach Monilca 

 in appearance, there can be little doubt that these merely represent in Cliloro- 

 storna the result of the same dynamic influences which in the exotic Gibbula 

 have resulted in the evolution of Monilea. 



Chlorostoma (Omphalius) exoletum Conrad sp. 



Plate 17, figures 4, 4 a. 



Monodonta exoluta {sic) Conr., Proc. Acad. Nat. Sci. i. p. 309, 1S43 ; Monitia do. Conr., 



Proc. for 1862, p. 569, 1S63 (error typogr. for exoleta). 

 Turbo heliciformis Heilprin, Trans. Wagner Inst. i. p. 113, pi. 16, fig. 55, 1887. 



Older Miocene of the Orthaulax bed. Ballast Point, Tampa Bay, VVillcox 

 and Burns ; and the equivalent stratum at Alum Bluff, Chattahoochee River, W. 

 Fla., Burns (van limatitni) ; Newer Miocene or Chesapeake beds on the Cape 

 Fear River, at Mrs. Purdy's marl-beds, Johnson ; at the Natural Well, Duplin 

 Co., N. Car., Burns ; and at Shell Branch, near Darlington, S. Car., Burns. 



This species, somewhat variable within certain limits, does not appear in 

 the Caloosahatchie Pliocene nor in the recent fauna. It is rather uniformly 



