﻿GEOLOGY AND PALEONTOLOGY OF THE CANAL ZONE. 



549 



Upper Cretaceous is not improbable as the age of the Bas Obispo 

 formation. 



Oligocene. 



bohio conglomerate. 



This is the oldest formation in which fossil organisms were found 

 within the Canal Zone. The fossil plant, Taenioxylon multiradiatum 

 Fehx, collected in a railroad cut on Bohio Ridge, is said by Doctor 

 MacDonald to come from the Bohio conglomerate. Should the spec- 

 mens really come from the Bohio conglomerate, it is probable that 

 that formation is of Ohgocene age. Taenioxylon multiradiatum, 

 according to Professor Berry, is also found in the Culebra and Cucu- 

 racha formations, both of which are of Ohgocene age, should the 

 Aquitanian be considered uppermost Oligocene instead of basal 

 Miocene. 



LIMESTONE OX HAUT CHAGRES. 



H. Douville has pubhshed the following interesting note: "Un 

 autre 6chantillon du Haut Chagres est representees par un calcaire 

 plus compacte prenant bien le poli ; il renforme 6galement de petites 

 Nummuhtes et de grandes L^pidocychnes voisines de L. cTiaperi, 

 mais en outre, de petites Orbitoides qui sont des Orthophragmina 

 ^toilees (Asterodiscus). C'est la m^me association que celle que 

 nous avons signalee a la base du stampien [ = Lattorfian], dans I'iie 

 de la Trinity. , . Nous avons ainsi dans le Haut Chagres un niveau 

 stampien inferieur. " ^ 



This corresponds to a horizon within the Vicksburg group. It is 

 probable that the rocks underlying part of the area around Alahajuela 

 mapped by Doctor MacDonald as Emperador hmestone are really of 

 this age. 



LIMESTONE AT DAVID. 



A similar forminiferal fauna occurs in the river bed, just above 

 the ice plant in David, station 6512; at station 6526, which, accord- 

 ing to Doctor MacDonald's section, is on the bed immediately next 

 below the one exposed at station 6512; and at station 6523, 2 miles 

 north of David. The following are the species reported by Doctor 

 Cushman: 



LARGER rORAMINIFERA PROM DAVID. 



Name. 



Station 

 6512. 



Station 

 6526. 



Station 

 6523. 



Nummulites davidensis Cushman 



Lepidocyclina macdonaldi Cushman . . 



duplicata Cushman. . . 



panamensis Cushman. 



sp 



Orthophragmina minima Cushman... 



(^Asterodiscus) sp 



» Soc. g(Solog. France, Comptes rend, stance No. 16, 1915, p. 130, 1918. 



