GEOLOGY AND PALEONTOLOGY OF CANAL ZONE


show that a considerable part of the umbilicus is not filled.
 This neverite is considered a subspecies of N. bolivarensis Clark (Clark and Durham, 1946, p. 16, pl. 15, figs. 10, 11, 14, 15, 18-20, 22, 26)-a subspecies characterized by its depressed outline and wide umbilical space gradually tapering toward the parietal callus. The specimen of N. bolivarensis proper shown by Clark on plate 15, figure 11, is depressed and has a wide umbilical space. The umbilical space, however, separates the callus from the entire umbilical wall. N. bolivarensis proper occurs in the late Eocene of Colombia. It and the subspecies from Panama are related to N. subreclusiana (Olsson) (1931, p. 68, pl. 10, figs. 1, 4), of the late Eocene or early Oligocene Chira shale of Peru'. That species has a high spire and practically filled umbilicus.
 Occurrence: Marine member of Bohio(?) formation (late Eocene or early Oligocene), Gatun Lake area, localities 40, 40a, 40d, 41 (immature).
 Neverita (Glossaulax) reclusiana xena Woodring, n. subsp.
 Plate 21, figures 5, 8, 9
 Of medium size, generally low spired. Spiral lineation visible on umlbilical wall, but not elsewhere, presumably due to slight wear. Posterior lobe of umbilical callus longer than anterior lobe, reaching umbilical wall. Space between umbilical wall and anterior lobe of umbilical callus narrow or very narrow.
 Height 25 mm, diameter 27 mm (type). Height 34 mm, diameter (incomplete) 35 mm (figured large highspired specimen).
 Type: USNM 561355; paratypes, Stanford Univ.
 Type locality: 137 (USGS 16911, Transisthmian Highway, 1.7 kilometers northwest of Sabanita, PanamA), lower part of Gatun formation.
 Neveriia reclusiana zena is based on 12 specimens from the lower part of the Gatun formation and one from the middle part. It is remarkably similar to a small form of N. reclusiana (Deshayes) found along the outer coast of Baja California and along the Gulf of California. The Gatun neverite in general has a narrower space between the umbilical wall and the anterior callus lobe. Some small Recent shells, however, are practically indistinguishable from the fossils. This Mexican form has been listed as a variety of N. reclisiana (Pilsbry and Lowe, 1932, p. 126), but its status is not yet satisfactorily determined.
 Typical species of Glossaulax are found in the Miocene of Florida and the Caribbean region: N. chipolana (Dall) (Gardner, 1926-47, p. 551, pl. 59, fig. 22, 1947; Chipola formation, Florida), N. subporcana (F. Hodson) (Hodson, Hodson, and Harris, 1927, p. 70, pl. 36, fig. 3, pl. 37, figs. 5, 9, 16; Miocene, Venezuela), and N.


cuspidata (Guppy) (Maury, 1925, p. 239, pl. 40, figs, 9, 10; Rutsch, 1942, p. 140; Springvale formation, Trinidad). N. chipolana has a short anterior callus lobe; N. subporcana has a narrow anterior lobe and the posterior lobe leaves part of the umbilicus unfilled; N. cuspidata is very large (height 60 mm) and has short subequal lobes. There are no living species of Glossaulax in the Caribbean Sea or elsewhere in the western Atlantic. The late Miocene N. cuspidata is the last Caribbean species.
 Inasmuch as N. reclusiana has a long history in the eastern Pacific going back to the Miocene, if not earlier, N. reclusiana xena evidently is a migrant from the Pacific. The present distribution of N. reclusiana and its allies, which are not found south of the Gulf of California, shows a marked reduction since Miocene time.
 Occurrence: Lower and middle parts of Gatun formation (middle Miocene). Lower part, localities 136a, 137, 137a. Middle part, eastern area, locality 155.
 Subgenus Hypterita Woodring, n. subgen.
Type: Natica helicoides Gray, Recent, Baja California to Perd.
 Hypterita is proposed for neverites that are greatly depressed, and have a very wide umbilicus with gently sloping wall, a thin umbilical callus lobe perched on a narrow or moderately wide umbilical rib, and a very thin wash of parietal callus. This well defined group of neverites includes only two known species: the type species and the Miocene Caribbean Neverita nereidis. The type species is generally known as Neverita glauca (Lesson).
 Neverita (Hypterita) helicoides (Gray)
 Plate 18, figures 15, 16
Natica patula G. B. Sowerby, Zool. Jour., vol. 1, p. 60, pl. 5,
 fig. 4, 1824 (Recent, locality unknown, but another specimen cited as South American). Barnes, Lyceum Natural History New York Annals, vol. 1, p. 136, 1824 (Recent, Perd). Not
 Natica patula J. Sowerby, 1822.
Natica helicoides Gray, Zool. Jour., vol. 1, p. 511, footnote, 1825
 (cited as manuscript name of Barnes).
Natica glauca "Humboldt", Lesson, Voyage autour du
 monde * la Coquille *, Zoologie, vol. 2, pt. 1, p. 369, pl. 11, figs. 1, 1', 1830 (Recent, Perd). Naica bonplandi Valenciennes, in Humboldt and Bonpland,
 Voyage aux rgions equinoxiales du nouveau continent, pt. 2, Recueil d'observations de zoologie, vol. 2, p. 264, pl. 57, figs. 3s, 3b, 1832 (Recent, Acapulco, Mexico; not seen). ?Neverita nereidis Maury, Olsson, Bull. Am. Paleontology, vol. 9, no. 39, p. 158, 1922 (Miocene, Costa Rica). Polinices (Neverita) glauca Humboldt, Olsson, idem, vol. 27, no.
 106, p. 20 (list), 1942 (Pliocene, Costa Rica).
Polinices helicoides (Gray), Hertlei and Strong, Am. Mus.
 Natural History Bull., vol. 107, art. 2, p. 287, 1955 (Recent, Baja California to Perd; see this publication for other citations).


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