GASTROPODS: TROCHIDAE TO TURRITELLIDAE


 Subgenus Subclimax Pilsbry and Olsson
 Pilsbry and Olsson, Bull. Am. Paleontology, v. 33, No. 135, p. 5, 1950.
 rype (orthotype): Anticlimax hispaniolensis Pilsbry and Olsson, Miocene, Dominican Republic.
 Subclimax, which is somewhat intermediate between Anticlimax s.s. and dome-shaped species of Teinostoma, has the umbilicus partly or completely closed by a wide umbilical callus. It has, however, axial undulations or folds of varying strength on the base, like those of Anticlimax s. s. The earliest species, occurring in the early Miocene Baitoa formation of the Dominican Republic, is of the same age as the earliest species of Anticlimax s. s. Subclimax is living in the western Atlantic and the eastern Pacific.

 Anticlimax (Subclimax) teleospira hystata Woodring, n. subsp.
 Plate 18, figures 1-3
 Dome-shaped, base slightly inflated. Periphery bluntly angular, except near outer lip, where it is drawn out into a ledge. Upper surface sculptured with faintly punctate spiral striae, which are indistinct or absent on middle third of body whorl and near outer lip. Base sculptured with faintly punctate spiral striae that disappear near umbilical margin and toward aperture, except on peripheral ledge. Base also bearing faint crude axial undulations. Umbilical callus filling umbilicus, except a narrow niche adjoining parietal callus. Junction of outer and basal lips drawn out in an ,angular thickened spoutlike projection, broken on type.
 Height 1.5 mm, diameter (incomplete) 2.7 mm
-(type).
 Type: USNM 561319.
 Type locality: 185 (USGS 8383, Caribbean coast, west of Rio Miguel, station 26 plus 100 feet (30 m) Panamd), upper part of Gatun formation.
 Anticlimax teleospira hyslata is represented by two ,specimens from the upper part of the Gatun formation in the coastal area west of the Canal Zone. The spoutlike projection of the peristome is like the projection of the type of Teinostoma. It is broken on the type but preserved on the other specimen, which is otherwise less complete. A. teleospira proper (Pilsbry and Olsson, 1950, p. 10, pl. 2, figs. 7, 7a), which occurs in the lower part of the Gatun formation but is not represented in the U. S. National Museum collections, has a carinate periphery and stronger basal undulations.
 The closely related A. tholus (Pilsbry and MeGinty) (1945-50, pt. 3, p. 79, pl. 8, figs. 1, la, 1b, 2, 2a, 1946), a Recent species from Florida, has stronger spiral sculpture and lacks the extended peristome. An undescribed species, dredged at a depth of 6 to 9 fathoms off Beaufort, N. C., has a more angular periphery,


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narrower umbilical callus, and lacks the extended peristome. A. willetti Hertlein and Strong (1940-51, Pt. 10, p. 112, pl. 9, figs. 13-15, 1951), from the Pacific coast of Costa Rica, is larger and has stronger basal undulations. The only other recorded Miocene species of Subclimax, A. hispaniolensis Pilsbry and Olsson, has a sunken apex and axial undulations on the upper surface of the body whorl. Both Gatun species of Anticlimax are more similar to Recent species than to contemporaneous or slightly older Miocene species in the Caribbean region so far described.
 Occurrence: Upper part of Gatun formation, western area (late Miocene), locality 185.

 Genus Cyclostremiscus Pilsbry and Olsson
 Pilsbr and Olsson, Acad. Nat. Sci. Phila. Proc., v. 97, p. 266,
 1945.
 Type (ortlhotype): Vitrinella panamesis C. B. Adams, Recent,
 Pacific coast of Panamd.
 Subgenus Ponocyclus Pilsbry
 Pilsbry, Acad. Nat. Sci. Phila. Mon. 8, p. 426, 1953. Type (orthotype): Adeorbis beauii Fischer, Recent, Florida and
 West Indies.
 Ponocyclus lacks the axial sclptaire of the subgenus Cyclostremiscus s. s. Some species, however, are more or less intermediate and Pilsbry realized that the name Ponocyclus may eventually be found to be superfluious.
 Cyclostremiscus (Ponocyclus) pentagonus (Gabb) Plate 17, figures 7-15
Cyclostrema pentagona Gabb, Am. Philos. Soc. Trans., n. ser.,
 v. 15, p. 243, 1873 (Miocene, Dominican Republic).
Vitrinella pentagona (Gabb), Gabb, Acad. Nat. Sci. Phila. Jour.,
 2d ser., v. 8, p. 368, pl. 47, fig. 68, 1881 (Miocene, Dominican
 Republic).
Cyclostrema quadrilineatum Toula, K. k. Geol. Reiclusanstalt
 Jahrb., Band 61, p. 497, pl. 31, figs. 1la-e, 1911 (Miocene,
 Canal Zone).
Circulus pentagona (Gabb), Pilsbry, Acad. Nat. Sci. Phila. Proc.,
 v. 73, p. 397, 1922 (Miocene, Dominican Republic).
'Circulus" pentagonus (Gabb), Woodring, Carnegie Inst. Washinagton Pub. 385, p. 441, pl. 37, figs. 16-18, 1928 (Miocene,
 Jamaica).
 Small, depressed, wlhorls 4%, the first 2% very slowly enlarging. Protoconch relatively large, rising abruptly. Body whorl bicarinate or, less conmmonly, tricarinate. Early whorls rounded between sutures. A carina appears on later half of penult about midway between sutures and forms upper carina on body whorl. Basal carina generally weaker than upper. Periphery rounded, bluntly angular (the usual condition), or sharply angular, forming a third carina. A few specimens have one or more faint spiral threads on penult above carina, and a few have a low spiral thread on body whorl below and near upper carina or above and near lower carina. Umbilical wall bearing crude gen-