GEOLOGY AND PALEONTOLOGY OF THE CANAL ZONE. 91 



Orthophragmina minima, new species. Oligocene ?, station 6512, 

 river bed, David. 



Nummulites panamensis, new species. Oligocene, Culebra forma- 

 tion, stations 6024a, Rio Agua Salud ; 6025, Bohio Ridge switch ; 

 doubtfully at 6026, 2 miles south of Monte Lirio. 



Nummulites davidensis, new species. Oligocene?, stations 6512, river 

 bed, David; 6526, Chiriqui. 



OrMtolites americana, new species. Oligocene, Culebra formation, 

 Gaillard Cut at stations 6013, 60196, and 6020a. 



DESCRIPTIONS OF SPECIES. 



Family NUMMULITIDAE. 

 Genus LEPIDOCYCLINA. 



LEPIDCCYCLINA CANELLEI Lemoine and DouviHe. 



Plate 34, figs. 1-6. 



Lepidocyclina canellei Lemoine and Dottvjxle,. Mem. Soc. Geol. Prance, 

 Paleontologies Mem. 32, p. 20, pi. 1, fig. 1 ; pi. 3, fig. 5, 1904. 



Test comparatively small, diameter of largest specimens slightly 

 less than four millimeters, thickness a little more than one-fourth the 

 diameter; circular in outline, central portion somewhat raised and 

 evenly rounded, near the periphery flattened or even slightly con- 

 cave; surface in well preserved specimens finely granular or even 

 finely papillate, but not strongly so, often appearing smooth to the 

 unaided eye. In worn specimens the surface appears as a series of 

 regular hexagonal, honeycomb-like reticulations due to the edges 

 of the lateral chambers. 



In vertical section the lateral chambers are seen to be arranged in 

 vertical columns, one directly above the other, from the equatorial 

 chambers to the surface, about twelve chambers in each vertical col- 

 umn in the central region, the lateral walls hardly thicker than the 

 upper or lower surfaces. Chambers of adjacent columns arranged 

 alternately, no distinct columns present. Equatorial chambers grad- 

 ually increasing in size toward the periphery, single throughout, ex- 

 tending peripherally beyond the lateral chambers and in surface view 

 in well-preserved specimens appearing as a hexagonal reticulation. 

 Embryonic chambers nearly equal in size, nearly semicircular in sec- 

 tion, their common wall straight. 



Horizontal section showing the equatorial chambers regularly 

 hexagonal, those toward the periphery largest. Embryonic cham- 

 bers similar to those shown in the vertical view. 



Occurrence. — Lemoine and Douville described and figured this 

 species from Panama, from Penablanca, also noting it from Mar- 

 8370&— 18— Bull. 103 7 



