176 RELATION BETWEEN CLIMATE AXD VEGETATION 



the frontier as far as the Rio Grande * j\Iy first halt was at a 

 village founded by the Jesuits, and still enjoying a little pros- 

 perity. The province hereabouts resembles in its general 

 features many parts of Matto-Grosso. Here, as in tlie environs 

 of Pocone, we have vast plains periodically inundated and dotted 

 with Copernicias or spiny Mimosas : there we find the Campos 

 with its characteristic vegetation, or else an expanse of forest 

 more or less considerable in extent. Santa- Ana, San-Rafael, 

 San-Igiiacio, and San-iMiguel, which is the last mission I visited, 

 are connected with the capital of the department, Santa-Cruz de 

 la Sierra, by two roads ; of these, one runs along the frontier of 

 the country of Moxos and passes through tlie villages of Con- 

 cepcion and San-Xavier ; the other, more to the south, crosses a 

 country with scarcely a single inhabitant^ and tliis was tlie one I 

 too liastily chose. 



In trutli, the very first day I found myself on a soil which, 

 half covered with water, sank under the foot, and from which my 

 mules could with difficulty extricate themselves and get onwards. 

 My health, too, was failing me, but I managed, by travelling 

 14 or 16 hours a day, to get over 120 leagues of interesting 

 country. For tiie first few days I saw nothing but Pantanals, 

 with their never-ending Copernicias ; but here and there the 

 sameness was broken by some other plant. At a short distance 

 from San Miguel, I found in the woods which broke the Pan- 

 tanal a consideiable quantity of the large Cereus, which bore 

 at a height of 10 or 15 yards, its angular branches covered all 

 over with starry prickles ; then there was the Gayac, the wood 

 of which, known by the inhabitants of Chiquitos by the name of 

 Gicaiacum, is used for making drinking-cups, which are believed 

 to cure a virus that the people think is constitutional. But tiie 

 most characteristic tree of this country is the fine Mimosa called 

 Vinnl, the astringent leaves of which are much used in Bolivia 

 for the cure of ophthalmia. The trunk of this tree divides a 

 little above the ground, and tlie branches grow obliquely, which 

 makes a very fine head that can by its delicate tint be distin- 

 guished as far as the eye can reach. 



As the Copernicias disappear, another Palm, at first sight like 

 a small specimen of the preceding species, but distinguished 

 from it by the long prickles which clothe its stem, makes its 

 appearance. Tiiis small tree, called Saro ( Thrinax brasi- 

 liensis, Mart.), grows in dense closely-packed tufts, and with 



* This Rio Grande is the same as the Guapai, which more to the north 

 takes the name Mamore. and flows into the Guapoie and the Beni, which 

 together form the Itio Madeira, one of the principal tributaries of the 

 Amazon. 



