INSULATED ROCKS. 339 



towards one of its extremities, preceding, and announcing 

 in some sort, a great depression* of the chain. This phe- 

 nomenon is again observed in the group of the Parime, the 

 loftiest summits of which, the Duida and the Maraguaca, 

 are in the most southerly range of mountains, where the 

 plains of the Cassiquiare and the Rio Negro begin. 



These plains or savannahs, which are covered with forests 

 only in the vicinity of the rivers, do not, however, exhibit 

 the same uniform continuity as the Llanos of the Lower 

 Orinoco, of the Meta, and of Buenos Ayres. They are 

 interrupted by groups of hills (Cerros de Daribapa), and by 

 insulated rocks of grotesque form which pierce the soil, and 

 from a distance fix the attention of the traveller. These 

 granitic, and often stratified masses, resemble the ruins of 

 pillars or edifices. The same force which upheaved the 

 whole group of the Sierra Parime, has acted here and there 

 in the plains as far as beyond the equator. The existence of 

 these steeps and sporadic hills, renders it difficult ^ determine 

 the precise limits of a system in which the mountains are 

 not longitudinally ranged as in a vein. As we advance 

 towards the frontier of the Portuguese province of the Kio 

 Negro the high rocks become more rare, and we no longer 

 find the shelves or dykes of gneiss-granite which cause rapids 

 and cataracts in the rivers. 



Such is the surface of the soil between G8i and 70J- 

 of longitude, between the meridian of the bifurcation of the 

 Orinoco, and that of San Fernando de Atabapo; further on, 

 westward of the Upper Kio Negro, towards the source of 

 that river, and its tributary streams the Xie and the Uaupes 

 (lat. 1 2, long. 72 74) lies a small mountainous table- 

 land, in which Indian traditions place a Laguna de oro, that 

 is a lake, surrounded with beds of auriferous earth.f At 

 Maroa, the most westerly mission of the Kio Negro, the 

 Indians assured me that that river, as well as the Inirida (a 

 tributary of the Guavare), rises at the distance of five days' 



* As seen in Mont Blanc and Chimborazo. 



t According to the journals of Acunha and Fritz, the Manao Indians 

 (Manoas) obtained from the banks of the Yquiari (Iguiareor Iguare), gold 

 of which they made thin plates. The manuscript notes of Don Apolli- 

 nario also mention the gold of the Rio Uaupes. (La Condamine, Voyage 

 A 1' Am ozone.) We must Dot confound tbe Laguna de Oro, which is said 



Z2 



