ORTMANN I TERTIARY INVERTEBRATES. 169 



Miocene of Virginia, which differs, however, in the more strongly angu- 

 lated periphery, flatter whorls and coarser threads, and C. metriiim Dall 

 (p. 394, pi. 22, f. 27) from the older Miocene of Florida, which differs in 

 the flat whorls and the finer sculpture. 



101. CALLIOSTOMA IHERINGI Ortmann. 



PI. XXXI, Fig. 7"'". 

 1900 C. i. Ortmann, in: Amer. Journ. Sci., v. 10, p. 373. 



Shell conical, broader than high, scalariform, umbilicated. Six whorls, 

 which are sharply angulated ; one angulation is formed by a sharp revolv- 

 ing keel in the upper part of the whorls, a second one exposed only on 

 the last whorl is formed by a keel on the periphery. Suture distinct, 

 forming an obtuse angle ; upper part of whorls (above upper keel) oblique, 

 flat, with 5 to 6 revolving threads, which are slightly granulated ; lower 

 part (below that keel) vertical, slightly concave on the last whorl, with 5 

 to 7 fine, smooth threads. Base of shell slightly convex, depressed toward 

 the umbilicus, which is moderately large. About 18 revolving threads on 

 the base, which are smooth, more crowded and finer toward the periphery, 

 a little stronger near the umbilicus, where the intervals are about as broad 

 as the threads. 



Height, 9.5 mm; diameter, 12 mm. 



Remarks: The presence of an umbilicus brings this species into the 

 subgenus E^ltrochus. 



Record of specimens : Mouth of Santa Cruz River, i sp. 



'Affinities: A species that resembles this one in the presence of two 

 angulations on the last whorl, and belongs also to the subgenus Eutrochiis 

 is: C. cychis Dall (1892, p. 403, pi. 23, f. 20) from the Miocene of North 

 Carolina, but this one is much lower. Another species with the same 

 double angulation and open umbilicus is Trochiis biangnlattis Eichw. (see : 

 Hoernes, 1856, p. 460, pi. 45, f. 5) from the Miocene of Europe, but it is 

 much higher. The latter species is said to be identical with T. ditropis 

 Wood (1848, p. 133, pi. 14, f. 9) from the Pliocene of England. The 

 latter, however, in external form, is more like our Patagonian fossil, being 

 less high than the Miocene form, and it differs from C. iheringi in the 

 upper angulations being more prominent, the number of revolving threads 

 being different, especially on the base, which is said to be finely imbricated. 



