224 



Bulletin 39 



396 



iolana Maury of the Cercado formation of Santo Domingo but 

 the main difference lies in their dorsal areas, that of hispaniolana 

 Maury being sculptured more or less like the rest of the shell; 

 in bocasensis, as described above, the sculpture of the dorsal area 

 is dominantl}^ concentric, only the upper half bearing 2 or 3, low 

 but scabrous radials. 



Gaiu7i Stage: Bocas del Toro. 



Subgenus PARV§ LUCIRA, Ball 



Section BELLUClf^A, Ball 



Phacoides actinus Dall Plate 32, figure 24 



Phacoides {Bellucina) actinus Dall, 1903, Trans. Wagner Free Inst. 

 Sci., vol. 3, pt. 6, p. 1385, pi. 52, fig. 3. 



Dall gives for his typical specimens from the Bowden beds 

 of Jamaica, a height of 4.50 mm, while the Panama shells, all 

 from Bocas Island, do not exceed 3 mm in height but agree in 

 other respects. It is also recorded by Maury from the upper 

 part of the Cercado formation of Santo Bomingo. 



Gatun Stage: Bocas del Toro. 



Genus DIVARICELLA, von Martens 



Divarlcella quadrisulcata d'Orbigny Plate 32, figure 20 



Lucina divaticata Conrad, 1840, Fossils of the Medical Tertiary, p. 39, 



pi. 20, fig. 3, but not of Linne. 

 Lucina quadrisulcata d'Orbigny, 1846, Voy. Am. Mer. , p. 584. 

 Divaricella quadrisulcata Dall, 1903, Trans. Wagner Free Inst. Sci. , 



vol. 3, pt. 6, p. 1389. 

 Lucina {^Divaricella) quadrisulcata Bose, 1906, Boll, de Inst. Geol. de 



Mexico, numero 22, p. 77. pi. 11, figs. 2, 3. 



This species is very rare in Costa Rica. The shells are rath- 

 er thin and generally more finely sculptured and approach in 

 this respect the D. compsa Ball of the Florida Pliocene. Our 

 larges specimen measures: height 14 m, length 10 mm, diameter 



