228 



quiare, and the Rio Negro, is an immense 

 plain, covered partly with forests, and partly 

 with grasses. Small rocks rise here and there 

 like castles. We regretted, that we had not 

 stopped to rest near the rock of the Tiger ; for 

 in going up the Atabapo we had great difficulty 

 to find a spot of dry ground, open and spacious 

 enough to light fires, and place our instruments 

 and our hammocks. 



April 28th. It rained hard from sunset, and 

 we were afraid that our collections would be 

 damaged. The poor missionary had his fit of 

 tertian fever, and besought us to reembark im- 

 mediately after midnight. We passed at day- 

 break the Piedra and the Raudalito* of Gua- 

 rinuma. The rock is on the east bank ; it is a 

 bar§ shelf of granite covered with psora, clado- 

 nia, and other lichens. I fancied myself trans- 

 ported to the north of Europe, and on the ridge 

 of the mountains of gneiss and granite between 

 Freiberg and Marienburg in Saxony. The cla- 

 donias appeared to me to be identical with the 

 lichen rangiferinus, the 1. pixidatus, and the 1. po- 

 lymorphus of Linneus. After having passed the 

 rapids of Guarinuma, the Indians showed us in 

 the middle of the forest, on our right, the ruins 

 of the mission of Mendaxari. which has been long 

 abandoned. On the east bank, near the little 



* The rock and little cascades. 



