COROCORO COPPER DISTRICT OF BOLIVIA 89 



more dissimilar than the West Indian species previously 

 enumerated. Other existing South American species which 

 I have not seen include Polystichum dubiitm (Hoker) Diels 

 of the Andes of Ecuador and Peru, which is markedly dif- 

 ferent from the fossil in its pinnate and anastomosing 

 veinlets. Another variable form Polystichum denticiilatum 

 (Swartz) J. Smith of neotropical South America has 

 reduced forms in the higher Andes, as, for example, the 

 var rigidissimum described by Hooker from Colombia : 

 but this type also seems to be remote from the fossil. 



The resemblances between the fossil form and still exist- 

 ing West Indian species I regard as valid evidence of 

 relationship, and while it is probable that the types men- 

 tioned from the latter region are represented in the rain- 

 forest along the eastern foothills of the present Andes, this 

 resemblance is sufficient, it seems to me, to stamp the fossil 

 as a form that dwelt as either an epiphyte or a rock-dwelling 

 form in a region less desiccated and warmer than that 

 inhabited by such modern forms as Polystichum rnohrioides 

 (Bory) Presl of southern Chile and Patagonia, or Polys- 

 tichum denticulatum, var rigidissimum Hooker of the high 

 Andes of Colombia. 



This species is rather common at Potosi but apparently 

 rare in the Corocoro deposits. 



CONIFEROPHYTA 



Order TAXALES 



Family TAXACE^ 



Subfamily PODOCARPE.E 



Genus Podocarpus L'HERiTiER 



Podocarpu,s fossilis ENGELHARDT 



Podocarpus fossilis Engelhardt, Sitz. Naturw. Gesell. I sis in 

 Dresden, 1894, Abh. i, p. 5, pi. i, fig. 12. 

 Berry, Proc. U. S. Natl. Mus., vol. 54, p. 120, pi. 15, fig. 2, 1917. 



Description. Leaves sessile, linear-lanceleolate and fal- 

 cate in outline, acutely pointed at both ends. Margins entire. 



