FLOEA OF ARGENTINA. 



397 



such a tangle of sharp points that they form a veritable snare, in which animals 

 run the risk of perishing. 



The forests are not arrested abruptly on the verge of the pampas, into which 

 are projected wooded headlands and islands, while elsewhere grassy glades appear 

 amid the groves and thickets. Since the arrival of the Europeans the indigenous 

 herbaceous flora of the pampas has been invaded by numerous species introduced 

 from the Old World, which have rapidly spread from the seaboard to the foot of 

 the Andes. Thus several varieties of the thistle have taken possession of the 

 plains, where in dry seasons they grow so thickly as to be quite impenetrable. 



Fig. 162. — Floeas of the Plateaux and Ravines. 

 Scale 1 : 1,000,000. 





,p(J6Heral Ac^la,;\^»• e^ s'y--- ,4v 



¥'im 



38' 







famoa t^e /as Cornices 



r^.^p"S;>i^'*^,.^^% 



38° 



65° 



West or (jreernwich 



18 Miles. 



These European species would appear to have improved the pasturage by the de- 

 velopment of the ixiato hlando or pasto tierno, tender herbage good for sheep, with 

 a corresponding decrease of the jjf^^^o duro, or coarse grasses on which horses 

 chiefly graze. 



Compared with the other vegetable zones the pampas flora comprises but a 

 small number of species, which, however, are remarkable for their prodigious ex- 

 pansion. But the (/'/ncriuni argoiteiirn, known in Europe by the name of "pam- 

 pas grass," does not occur in the pampas proper, but only on the slopes of the 

 mountains, and in the moist barrancas or bottom-lands on the Patagonian frontier. 



