418 THE POLAR WORLD. 



Sterility on the land. Monotonous warra tints of brown, yellow, or light red 

 everywhere fatigue the eye, which vainly seeks for rest in the dark blue sky, 

 and finds refreshing green only on some river-banks. 



Many broad flat vales transsect the plains, and in these the vegetation is 

 somewhat better. The streams of former ages have no doubt hollowed them 

 out, for the rivers of the present day are utterly inadequate to the task. On 

 account of the dryness of the atmosphere, the traveller may journey for days 

 in these Patagonian plains without finding a drop of water. Springs are rare, 

 and even when found are generally brackish and unrefreshing. While the 

 " Beagle " was anchoring in the spacious harbor of Port St. Julian, a party one 

 day accompanied Captain Fitzroy on a long walk round the head of the harbor. 

 They were eleven hours without tasting any water, and some of the party were 

 quite exhausted. From the summit of a hill, to which the appropriate name 

 of " Thirsty Hill " was given, a fine lake was spied, and two of the party pro- 

 ceeded, with concerted signals, to show whether it was fresh water. The dis- 

 appointment may be imagined when the supposed lake was found to be a 

 snow-w^hite expanse of salt, crystallized in great cubes. 



The extreme dryness of the air, which imparts so sterile a character to the 

 country, favors the formation of guano deposits on the naked islands along 

 the coast, which are frequented by sea-birds. Protracted droughts are essen- 

 tial to the accumulation of this manure, for repeated showers of rain would 

 wash it into the sea, and for this reason no guano deposits are found on the 

 populous bird-mountains of the north. A similar dryness of the atmosphere 

 favors the deposit at Ichaboe on the African coast, at the Kooria Nooria Is- 

 lands in the Indian Ocean, and at the Chincha Islands on the Peruvian coast ; 

 and this kind of climate appears also to be particularly agreeable to the sea- 

 birds. 



Considering the excessive aridity of Patagonia, it seems surprising that the 

 country should be traversed from west to east by such considerable rivers as 

 the Rio Negro, the Gallegos, and the Santa Cruz ; but all these have their 

 sources in the Andes, and are fed by mountain torrents, which no doubt derive 

 their waters from the atmospherical precipitations of the Pacific. 



The zoology of Patagonia is as limited as its flora, and greatly resembles in 

 its character that of the mountain regions of Chili, or of the Puna or high ta- 

 ble-land of the tropical Andes of Peru and Bolivia, the height of which varies 

 from 10,000 to 14,000 feet above the level of the sea. 



In all these countries, situated in such different latitudes, the explorer is as- 

 tonished to find not only the same genera, but even animals of the same species. 

 The forest-loving race of monkeys is nowhere to be found in treeless Patago- 

 nia. Xone of the quadrumana ventures farther south than 29° lat., but on the 

 borders of the Rio Negro, the northern boundary of Patagonia, some small bats 

 are seen fluttering about in the twilight. 



The dark-ljrown yellow-headed Gallctis vittata, an animal allied to the Civ- 

 ets and Genets, is likewise found there, but much more frequently its relation the 

 Zorilla, which ranges from 30° lat. to the Strait of Magellan, and, like the skunk 

 of the north, has the power of discharging a fluid of an intolerably fetid odor. 



