644 E. W. BERRY CERTAIN PLANT-BEARING BEDS IN SOUTH AMERICA 



correlated) transgression of what he calls the San Jorge formation, which 

 in the early Eocene flooded the east coast of southern Argentina and pene- 

 trated northwesterly up the Eoca A^alley. I mention this admirable con- 

 tribution in the present connection, since it has a bearing on the age and 

 antecedent history of the Magellanian beds. 



At Punta Arenas and elsewhere along the Straits of Magellan and at 

 various localities in Tierra del Fuego a series of sandy lignitic beds have 

 been described by Ortmann, Hatcher, Nordenskjold, and others, which 

 are of the greatest interest to paleobotanists because of the remarkable 

 flora contained near their base. The section, somewhat abbreviated, is 

 as follows : 



1. Sands, lignitic sandstone, and conglomerates = horizon V of Hatcher = 



Patagonian formation of Ortmann = Burdigalian. 



2. Sandstones with lignite beds and fossil plants = horizon IV of Hatcher = 



Upper lignites or Punta Arenas coal = Miocene Araucaria beds of Dusen 

 = Acquitanian. 



3. Sandstone with oyster beds = horizon III of Hatcher = Oligocene. 



4. Sandstones with fossiliferous calcareous lenses = Oligocene. 



5. Fossiliferous beds = horizon II of Hatcher = Oligocene. 



6. Sand and sandstone with fossiliferous calcareous concretions and fossil 



plants = horizon I of Hatcher = Oligocene Fagus zone of Dusen = 

 Oligocene. 



7. Lignitic shales = Lower lignites of Hatcher = Oligocene (?). 



This section presents the record of a minor oscillation of the strand- 

 hne with continental deposits passing into lagoonal, and these into littoral 

 and shallow-water marine, and then gradually shallowing and perhaps 

 becoming emergent during the Aquitanian, followed by a marked trans- 

 gression in the Burdigalian. At present our chief interest centers in the 

 Fagus zone and its flora. This flora, as described by Dusen,^® consists of 

 29 species, of which the Flabellaria, previously mentioned as doubtful, is 

 the only one that occurs in the Tertiary floras already enumerated from 

 South America. The particular facies of this flora is furnished by the 

 abundance of Fagacese. This family is represented by two species of 

 Fagus and by 13 species or varieties of Nothofagus. This flora is cer- 

 tainly older than those already mentioned and it is as certainly Tertiary 

 in age. It unquestionably had its beginnings in the Northern Hemi- 

 sphere and has also been found to be represented at somewhat similar 

 horizons in Australia, New Zealand, and Antarctica. That it did not 

 migrate into Patagonia from North America appears to be probable from 

 the absence of any definite ancestral assemblage in the abundantly fos- 



^5 p. Dusen : Ueber die tertiare Flora der Magellanslander. Svenska Exped. till Magel- 

 lanslanderna, Band 1, 1899, pp. 87-107, pis. 8-13. 



