948 PATAGONIAN EXPEDITIONS: BOTANY. 



Myrtaceae, and certain Coniferae ; and he would include in it with per- 

 austral America, southern parts of Australia, also Tasmania, New Zealand, 

 and the sporadic islands of the southern ocean (none of those with living 

 vegetation being within the antarctic circle). 



The Patagonian part of. this larger complex, has been compared to an 

 ovate leaf, its base about Sierra Ventana, in Southern Argentina, 38 S. 

 Lat., and extending across to Valdivia on the Chilian coast about 39. 

 The distance from this base to Cape Horn is nearly 1,000 miles (1,600 kil- 

 ometers). The leaf-pattern is unequal, having a broad eastern half, nearly 

 entire at its margin, and a narrow western half, jagged and torn up into 

 bits ; and the midrib, represented by the Cordillera, is itself double or 

 triple in its northward division, and is frequently cut across by rents, which 

 continue outwards to the margin^ as long, very meandering rivers. The 

 southern part, or leaf-point, is prolonged, and bent towards the east, and 

 greatly frayed and divided, longitudinally and transversely, as if breaking 

 to fragments. To drop the comparison with a leaf, we may merely indi- 

 cate the geological bearings of its structure, as being what remains of a 

 larger mainland which has been partly submerged, like what Scotland and 

 Scandinavia should be if certain changes which have befallen them had 

 been more intense. Viewed in this way, the islands and submarine banks 

 that remain southwards, as the South Shetland Isles, may be regarded as 

 the surviving rudiments of a drowned continent. These facts cannot here 

 be dwelt on, but must be kept in memory when considering questions of 

 distribution. In Vol. IV of this series of Reports Professor Ortman dis- 

 cusses the theory of Antarctica, or of former land-connections in tertiary 

 times, across the South-polar regions between Fuegia and Tasmania, pos- 

 sibly extending to South Australia, and approaching, though perhaps not 

 actually reaching New Zealand. Our knowledge of the southward islands 

 has been recently enlarged by the antarctic exploring expeditions. The 

 most interesting discovery has been of fossil pteridophytes and conifers of 

 palaeozoic age in the South Shetlands. 



The correlative exposures of the land east and west of the Andean 

 range, which is determining the political relations, as between Argentina 

 and Chili, seem largely to have determined the botany, and first of all 

 the climatic differences. And as the good climate, excessively moist, and 

 very rich for its vegetation, lies away from the foci of modern civilization, 

 and the eastern plains, very dry, and rocky, and treeless, are uninvit- 



