CHILE 



645 



siliferous Upper Cretaceous or Eocene of the latter continent from which 

 it seems probable that it could have been derived. ISTor are any traces of 

 it found at more northern localities in South America. The explanation 

 seems to be that it reached southern South America from the opposite 

 direction, namely, Antarctica. 



A very interesting Tertiary flora has been recently described^ *^ from the 

 border of the Antarctic continent on Seymour Island, off the east coast 

 of Graham Land. This flora contains a large element of subtropical 

 types like those found today in southern Brazil, and another large element 

 of forms suggestive of the existing temperate flora of southern Chile and 

 Patagonia, and including species of Fagus and Nothofagus like those 

 found in Patagonia, Chile, Australia, and New Zealand. Dusen, ignor- 

 ing the usually mixed climatic character of early Tertiary floras, and the 

 association of tropical and temperate types under favorable conditions of 

 humidity, and basing his conclusions on the broken character of the fossil 

 remains of these temperate types, reaches the conclusion that the tem- 

 perate and the subtropical elements were contemporaneous, but that the 

 latter were coastal forms under a subtropical climate, while the former 

 grew in the vicinity at elevations which he suggests amounted to 6,500 

 feet or more, and were brought by streams to the littoral basin of sedi- 

 mentation. If this is true, it indicates a considerable mountain chain of 

 the Andean type forming the axis of Graham Land at that time as it does 

 at present. The only evidence bearing on the age of the folding, which 

 may really have little bearing on the time of elevation, is the presence at 

 Hope Bay, on Graham Land, of an extensive late Jurassic fiora^^ found 

 in continental beds which are involved in this folding. Dusen concludes 

 that this Tertiary Antarctic flora is older than that of the Fagus zone of 

 the Magellanian beds. 



Poorly preserved mollusks associated with the plants are considered by 

 Wilckens to represent what he calls the Patagonian molasses, but since the 

 latter is more or less composite, as Windhausen^^ has shown, and incliides 

 faunal elements belonging to the lower Eocene San Jorge formation as 

 limited by the latter avithor, the evidence for the correlation adopted by 

 Andersson^'' can not be said to be conclusive. The presence of Zeuglodon 

 vertebrae, described from this locality by Wiman, should probably be con- 



^« p. Dus^n : tJber die Tertiare Flora der Seyraour-Insel. Wiss. Ergeb. Schwed. Siid- 

 polar-Exped., Band 3, 1008, 27 pp., 4 pis. 



" T. G. Halle: The Meso!!;oic flora of Graham Land. Swedish South Polar Expod., 

 1901-1003, Band 3, lief 4, 1913, 123 pp., pis. 



" Op. cit. 



" J. Gunnar Andersson : On the geology of Graham Land. Bull. Geol. Inst. Upsala, 

 vol. 7, 1906, pp. 10-71, pis. 1-6. 



