3^9 



Costa Rica Miockne — Olsson 



■157 



Domingo, Jamaica and Venezuela. It differs from the Gnppyana 

 by its closer and more irregular longitudinal sculpture crossed by 

 faint spirals, producing a cancellated appearance. The umbili- 

 cus is larger and more ample. 



Gatun Stage: Gatim, C. Z. 



Water Cay, Panama. 

 Banayia Riier, C. R. 



Genus POimiCES Montfort 



Polinices SUbcfausa Sowerby Plate 13, figures 16, 17 



iVatica snbdausa Sowerby, 1849, Quart. Jourii. Geol. Soc. London, 

 vol. 6, p. 51. 



Natica snbdausa Guppy, 1S66, Quart. Journ. Geol. Soc. London, vol. 



22, p. 290, pi. 18, fig. 8. 



Polinices subdausa Brown and Pilsbry, 1911, Proc. Acad. Nat. Sci, 



Philia., vol. 63, p. 560. 

 Polinices subdausa Maury, 1917, Bull, Amer, Pal., vol. 5, p. 300, pi. 



23, fig. 14. 



This is a common fossil in the Miocene of Santo Domingo 

 and Jamaica. The Costa Rican shells are small, the largest 

 specimen in our collection measuring only 17 mm in altitute. 



When viewed from the dorsal side, the shell has a distinct- 

 ly NeritaASk.^ aspect, due to its low spire, close coiling and rap- 

 idly enlarging whorls and appressed sutures. The umbilicus is 

 of medium size, expanding below. The inner lip is provided 

 with a thick, heavy callus wdiich joins above with the outer lip. 

 At the upper edge of the umbilicus, the callus carries a deep, 

 transverse groove, a most characteristic feature. 



Gatun Stage: Gatun, C. Z. 



Hill No. J, Banajia River, C. R. 



Polinices Staoisfas-Meunleri Maury Plate 13, figure 7 



Polinices Stanislas-^neunieri Maury, 1817, Bull. Amer. Pal., vol. 5, 

 p. 300, pi. 23, figs. 15, i6. 



