404 TRANSACTIONS OF THE WAGNER FREE 



Both the typical form and the variety tampaensis Conrad appear in the 

 Caloosahatchie beds, but none of the specimens of the typical kind, though 

 apparently adult, are as large as Antillean specimens from the present fauna. 



Calliostoma (Butrochus) armillatum T. & H. 



Trochus armi/laius Tuomey and Holmes, Pleioc. Fos. S. Carolina, p. 118, pi. 26, fig. 3, 



1856. 

 Zisyphinus armi/lalus Conr., Cat. Mioc. Sh., Proc. Acad. Nat. Sci. i852, p. 569, 1863. 



" Waccamaw District," S. Car., Tuomey and Holmes ; Chesapeake Mio- 

 cene of Duplin Co. N. Car., Burns; Miocene marl of Cape Fear River, at Mrs. 

 Guion's marl-bed, Johnson. 



This pretty little species is well distinguished by its depressed form, wide 

 umbilicus, and single, strong, usually beaded spiral thread near the suture, the 

 other threads on the spire being smaller and plain. 



Calliostoma (Butrochus) limulum n. s. 

 Plate 18, figure 7 a. 



Pliocene of th'e Caloosahatchie and Shell Creek, Fla. 



Shell small, conical, with six somewhat rounded whorls and a rather acute 

 tip, spirally sculptured ; nucleus very minute, smooth, remainder of the shell 

 with from four to six subequal, strong, very closely beaded threads, increasing 

 by intercalation, the new threads beginning as extremely fine, simple elevated 

 lines, and gradually becoming beaded, whence at certain stages of growth the 

 spirals have an alternated appearance ; there is a single strong or two smaller 

 plain peripheral threads without beading, the threads of the rather convex 

 rounded base are like those of the spire ; umbilicus small, deep, bordered by 

 a single stout thread ; pillar as usual, aperture rounded-quadrate, the outer lip 

 crenulated at the edge by the sculpture ; suture distinct ; periphery rounded. 

 Alt. 6 ; max. diam. of base 6 mm. 



This modest little shell is quite uniform in its characters, varying slightly 

 in the size of the umbilicus and the flatness of the spire and base, zs J2ijubinii7n 

 does. From the young oi jiijubimmi it is easily distinguished by its smaller 

 umbilicus, relative elevation, and mature aspect. 



Calliostoma (Butrochus) ceramicum n. s. 

 Plate 18, figure 10. 

 Older Miocene of the Chipola epoch at Ten-Mile Creek, near Bailey's 

 Ferry, Chipola River, N. W. Florida, F. Burns, U. S. Geol. Survey. 



Shell elevated-conic, strongly spirally sculptured with one small smooth 

 nuclear and eight subsequent whorls; spiral sculpture of four strong, squarish, 

 revolving ribs, with somewhat narrower channelled interspaces, crossed by 

 numerous deeply-impressed, evenly-spaced, oblique lines, in harmony with the 

 incremental lines, which produce an effect on the ribs between the intersec- 



