. Bulletins of American paleontology. â â I f*^ ^^ Polinices tumidus Polinices mizunamiensis. Sjii^y r % %r. Polinices flemingianus %iA \- ^ â .â¢â â ...^ Polinices mellosus Text-figure 19. âProtoconchs of (1) Polinices tumidus (Swainson. 1840), (2) P. mizunamiensis Itoigawa, 1960, (3) P. flemingianus (Recluz, 1844), and (4) P. mellosus (Hedley, 1924). Discussion. âNeverita is characterized by its globose to weakly depressed shell and massive umbilical callus that is not divided into two lobes by a transverse groove. Species of Neverita have Glossaulax-like shells but their umbilical calluses
. Bulletins of American paleontology. â â I f*^ ^^ Polinices tumidus Polinices mizunamiensis. Sjii^y r % %r. Polinices flemingianus %iA \- ^ â .â¢â â ...^ Polinices mellosus Text-figure 19. âProtoconchs of (1) Polinices tumidus (Swainson. 1840), (2) P. mizunamiensis Itoigawa, 1960, (3) P. flemingianus (Recluz, 1844), and (4) P. mellosus (Hedley, 1924). Discussion. âNeverita is characterized by its globose to weakly depressed shell and massive umbilical callus that is not divided into two lobes by a transverse groove. Species of Neverita have Glossaulax-like shells but their umbilical calluses are massive. Neverita eocenica (Nagao, 1928a) Plate 4, figures 13-15; Table 17 Polynices [sic] {Neverita) eocenica Nagao, 1928a, pp. 118-119, pi. 18, figs. 2a-3. Neverita eocenica (Nagao). Hatai and Nisiyama, 1952. pp. 235-236; Majima, 1988. te.\t-fig. Polinices (Glossaulax) eocenica Nagao. Oyama, Mizuno. and Saka- moto, 1960, p. 50. pi. 5, figs. 8a-b. \GPS 35699 (PI. 4, fig. 13). designated by Hatai and Nisiyama (1952, pp. 235-236), from sea cliff W of a 48 m high hill, about 250 m north of Takesaki, Koyagi-jima (Hatai and Nisiyama, 1952), Koyagi-machi, Nishi-Sonogi-gun, Nagasaki Prefec- ture, lower Eocene Futagojima Formation. globose, very small, spire weakly elevated; body whorl not greatly inflated, slightly but distinctly flattened above periphery; whorls four or more (apices of all examined specimens eroded), sculp- tured with incremental growth lines that are most dis- tinct below suture and on base; shell not greatly thick- ened. Parietal callus heavy, greatly filling posterior apertural angle; anterior lobe indistinct. Umbilicus narrowly open; umbilical wall smoothly merges with the body-whorl side without any angulation, orna- mented with distinct growth lines; umbilical callus greatly thickened, largely filling umbilicus except for anterior and left sides of umbilicus, and smoothly merges with parietal callus; callus
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