DUSEN : THE VEGETATION OF WESTERN PATAGONIA. 19 



Although the plant growth of the lower and middle parts of the Aysen 

 valley differs in some other respects also, besides the one just named, 

 from that of the coast district, it must be regarded in a general way as 

 belonging to the community of evergreen beeches. However, as I have 

 pointed out, we are quite justified in setting apart the vegetation of this 

 valley, and of others within the northern section of west Patagonia, as a 

 separate section of the community of evergreen beeches. This part may 

 appropriately be called the Quila formation. Even this is not uniform 

 throughout and might therefore be further subdivided, the vegetation of 

 the river-banks and islands, for instance, being very different from that of 

 other parts of the valley. But such a subdivision of the vegetation of the 

 Aysen valley into smaller sections I shall not now attempt, since it is not 

 necessary for my present purpose. 



A short journey up the river is sufficient to show how different its 

 vegetation is from that of the coast district. It exhibits forms which 

 could hardly be expected to occur here, and which agree better with the 

 flora of a tropical country than with that of temperate regions. In par- 

 ticular, it contains two species, G^^nnera chilensis Lam., and Chusquea 

 qnila Kunth, that remind one of the luxuriance and magnificence of the 

 tropical floras, the former growing here and there in groups on the river 

 bank, and extending as far up the river as the evergreen beeches. The 

 flower stalks of the first of these plants, which resembles a species of 

 R/ienui, are more than man-high, the diameter of its rounded, lobed 

 leaves frequently exceeding two meters. The Chusqiiea plays a dominant 

 part in making up the undergrowth, and fills, almost uninterruptedly, the 

 spaces between the trees of the park-like forest, forcing its way to the 

 river banks in compact masses. It is a grass four to five meters high, 

 with stalks standing close together, three to four centimeters thick and as 

 hard as bamboo, forming a great impediment to the traveller's progress 

 and, except in rare cases, necessitating the use of the axe. Of the density 

 of the undergrowth the following will give a good idea. Our expedi- 

 tion J occupied seven weeks in going from the mouth of the Rio Aysen to 



'The members of this expedition which was sent out by the Chilian government for the 

 delimitation of the frontier between Chili and Argentina, and the main object of which was to 

 ascertain the interoceanic water-shed of the district around the sources of the Rio Aysen were, 

 in addition to myself, Dr. Hans Steffen, leader; Mr. De Fischer, Danish cartographer, and 

 Messrs. Horn and von Bronsart Schellendorf, German officers. Besides, twenty-five Indians, of 

 more or less pure breed, were employed as porters and pioneers. 



