GASTROPODS: TROCHIDAE TO TURRITELLIDAE


spiral and another near middle of whorl are slightly stronger than others. Sculpture of early whorls and growth line unknown.
 Height (incomplete, 3+ whorls) 25 mm, diameter 15 mm.
 This species is represented by poorly preserved fragments from calcareous sandstone in the Gatuncillo formation of the Rio Frijol area. The slightly convex or flat whorls and the subequal spirals resemble features of the late Eocene Peruvian Turritella samanensis (Olsson, 1928, p. 65, pl. 14, figs. 3, 4, 6-8; 1931, p. 74), which is recorded from the late Eocene of Colombia (Clark, in Clark and Durham, 1946, p. 26, pl. 23, figs. 1, 4). T. masinguiensis Clark (in Clark and Durham, .1946, p. 24, pl. 23, figs. 3, 5-7, 9, 10), also from the late Eocene of Colombia, appears to be T. samanensis.
 According to Olsson, the early whorls of T. samanensis .have three spirals. Therefore it is unlikely that it is related to T. uvasana Conrad, of the Eocene of CaliVlornia, the early whorls of which have two spirals (Merriam, 1941, p. 89.) Probably it is a representative of Merriam's T. buwaldana stock (Merriam, 1941, p. 42).
 Occurrence: Gatuncillo formation (late Eocene), Rio Frijol area, locality 34.
 Subgenus?
 Turritella species
 Large, slender. Late whorls slightly concave, a narrow carina lying near anterior suture and a wider carina near posterior suture. Intermediate whorls sculptured with a spiral at anterior third, one or two spirals at posterior third, and microscopic minor spirals. Sculpture of early and late whorls and growth line unknown.
 Height (incomplete, 3 whorls) 43 mm, diameter 24 mm.
 The affinities of this species, which occurs in the Gatuncillo formation, are undetermined. Late whorls are represented only by molds.
 Occurrence: Gatuncillo formation (late Eocene), Madden basin, localities 12, 15; Rio Frijol area, localities 32, 34.
 Subgenus? (Merriam's T. uvasana stock)
 Turritella adela Woodring, n. sp.
 Plate 15, figures 5, 6
 Turitella gatunensis Conrad, Dall, Wagner Free Inst. Sci. Trans.,
 v. 3, pt. 2, p. 310 (part, not pl. 17, fig. 10=T. atacta Dall), 1892 (Miocene, Vamos Vamuos, Panam). Dall, in Hill, Mus. Comp. Zool. Harvard College Bull., v. 28, p. 273 (part),
 1898 (list; Eocene, Vamos Vamos, Panami).
 Of medium size, slender. Whorls moderately con, vex. Sculpture of late whorls consisting of 9 or 10 primary spirals, the 3 or 4 on anterior half of whorls


slightly stronger than those on posterior half. Minor spirals of unequal strength lie between primaries. Earliest preserved whorls sculptured with two spirals: One at middle of whorl, the other midway between it and anterior suture. Spirals persist as the posteriormost and third (numbered anteriorly from middle of whorl), respectively, of the strong spirals on anterior half of late whorls. Base sculptured with numerous minor spirals of unequal strength and two stronger spirals adjoining periphery. Growth-line sinus moderately deep, the apex at middle of whorl; growth-line angle narrow.
 Heigh t (incomplete) 25 mm, diameter 7.5 mm (type). Height (incomplete, 3 whorls) 22.5 mm, diameter 12 mm (paratype).
 Type: USNM 561370; paratype, USNM 561371.
 Type locality: 41 (USGS 17716, east side of promontory 375 meters southeast of Palenquilla Point, Canal Zone), marine member of Bohio(?) formation. Turritella adela is abundant in the marine member of the Bohio(?) formation near Palenquilla Point and at the nearby submerged Vamos Vamos locality. All the specimens, however, are incomplete. In general features it resembles T. galvesia Olsson (1931, p. 78, pl. 14, figs. 2-7), of the Oligocene of Perd, but has more inflated whorls and a deeper growth-line sinus. The lower limb of the sinus of T. galvesia is practically vertical. The sculptural pattern and growth line of the Oligocene Venezuelan T. andreasi Hodson (1926, p. 37, pl. 24, figs. 7-9, 12, pl. 25, fig. 2) suggest relationship. Though the early sculpture of T. andreasi is unknown, intermediate whorls do not have the two strong spirals characteristic of T. adela at the same diameter.
 The early sculpture, the subsequent sculptural pattern, and the growth line indicate that T. adela is a medium-sized late Eocene or early Oligocene species of Merriam's T. uvasana stock, which reached its acme in the Eocene of the Pacific coast of North America and continued through the Oligocene (Merriam, 1941, p. 42-44). Dall identified T. adela as T. gatunensis Conrad. If he had specimens from Vamos Vamos in mind, he was justified in claiming that his T. gatunensis is closely related to T. uvasana.
 Occurrence: Marine member of Bohio(?) formation (late Eocene or early Oligocene), Gatun Lake area, localities 40, 40a, 40d, 41.
 Turritella meroensis Olsson
 Plate 15, figure 19
Turritella gatunensis Conrad, Joukowsky, Soc. Phys. Histoire
 Nat. Geneva Mm., v. 35, p. 163 (list), pl. 6, figs. 26, 27, 1906
 (Oligocene, Panami).
Turritella meroensis Olsson, Bull. Am. Paleontology, v. 17, no
 63, p. 76, p1. 13, figs. 1-4, 1931 (Oligocene, Perd, Ecuador),


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