126 CHARLES DARWIN 



ance of payment: it was only the high sense of hospitality, 

 which every traveller is bound to acknowledge as nearly uni- 

 versal throughout these provinces. After galloping some 

 leagues, we came to a low swampy country, which extends 

 for nearly eighty miles northward, as far as the Sierra Ta- 

 palguen. In some parts there were fine damp plains, covered 

 with grass, while others had a soft, black, and peaty soil. 

 There were also many extensive but shallow lakes, and large 

 beds of reeds. The country on the whole resembled the bet- 

 ter parts of the Cambridgeshire fens. At night we had some 

 difficulty in finding amidst the swamps, a dry place for our 

 bivouac. 



September i5th. Rose very early in the morning and 

 shortly after passed the posta where the Indians had mur- 

 dered the five soldiers. The officer had eighteen chuzo 

 wounds in his body. By the middle of the day, after a hard 

 gallop, we reached the fifth posta : on account of some diffi- 

 culty in procuring horses we stayed there the night. As this 

 point was the most exposed on the whole line, twenty-one 

 soldiers were stationed here; at sunset they returned from 

 hunting, bringing with them seven deer, three ostriches, and 

 many armadilloes and partridges. When riding through the 

 country, it is a common practice to set fire to the plain ; 

 and hence at night, as on this occasion, the horizon was 

 illuminated in several places by brilliant conflagrations. 

 This is done partly for the sake of puzzling any stray In- 

 dians, but chiefly for improving the pasture. In grassy 

 plains unoccupied by the larger ruminating quadrupeds, it 

 seems necessary to remove the superfluous vegetation by fire, 

 so as to render the new year's growth serviceable. 



The rancho at this place did not boast even of a roof, 

 but merely consisted of a ring of thistle-stalks, to break 

 the force of the wind. It was situated on the borders of an 

 extensive but shallow lake, swarming with wild fowl, among 

 which the black-necked swan was conspicuous. 



The kind of plover, which appears as if mounted on 

 stilts (Himantopus nigricollis), is here common in flocks of 

 considerable size. It has been wrongfully accused of in- 

 elegance; when wading about in shallow water, which is its 

 favourite resort, its gait is far from awkward. These birds 



