Z PROCEEDINGS OF THE JSTATlOiSrAL MUSEUM vol. to 



part of the surface in most of the speciments, is seen, in broken speci- 

 mens, to be calcified for a thickness of between 2 and 3 mm., and to be 

 rather prominently and transverseW reticulate rugose. The interior 

 is filled with a structureless calcareous matrix and suggests that the 

 nuts W'Cre single seeded. 



The equatorial outline of these fruits is approximately circular, 

 and they appear to have been practically symmetrical around the 

 polar axis, although some speciments appear to indicate a slight dis- 

 tal curvature. The proximal end is usually broken or incrusted with 

 matrix, but in one specimen (fig. 4) is seen to be perforated by a 

 large excentrically located hole. None of the specimens are suffi- 

 cient to show the presence or absence of the two other perforations 

 so frequent in this tribe. 



Cotypes.—Q2X. No. 37194, U.S.N.M. 



The relatively enormous thickness of the Tertiary in northwestern 

 Peru west of the present Andes has led Bosworth - to predicate not 

 only the existence of the mountains in Eocene times as the source of 

 the large amount of relatively coarse material that make up so much 

 of these sediments, but also his belief that the climate at that time 

 approached that of the present in this region in its aridity, a neces- 

 sary correlary. 



These abundant palm nuts offer some, though it must be con- 

 fessed rather inconclusive evidence on this point. It is recognized 

 that they might have been carried for considerable distances by 

 either rivers or ocean currents. Astrocaryuin fruits are not uncom- 

 mon in the present sea drift on the Pacific coasts of Panama and 

 Colombia, and if the currents were running in the right direction 

 in the Eocene, as they do at the present time, these nuts could have 

 been transj^ortecl for considerable distances along the middle Eo- 

 cene coast, and need not have grown in the immediate vicinity of 

 where the}^ are now found. 



Possibly bearing upon this point are the results of certain unpub- 

 lished studies by Dr. W. P. Woodring, which seem to indicate that 

 the Tertiary Caribbean fauna did not cross the Isthmus of Panama 

 or Central America to any appreciable extent when seaways were 

 developed between the Atlantic and Pacific oceans because of the 

 Pacific equatorial countercurrent and the greater tides of the Pacific 

 in this region ; and that the more tropical elements in the so-called 

 Caribbean Tertiary faunas were of Pacific origin and indigenous 

 on the west coast of tropical America. 



The warm shore current that at the present time is an offset 

 from the Pacific equatorial countercurrent, and which skirts the 

 Colombian and Ecuadorian coasts, is known locally as El Nino. Its 



=* Bosworth, T. O., Geology of the Tertiary and Quaternary Periods in the Northwest 

 Part of Peru. London, 1922. 



