72 DK. B. SPKUCE ON EQUATOEIAL-AMEKICAN PALMS. 



Situations 



of Sautarem, which is the furthest point "westward where I have 



seen it. 



§ 3. I^alms of the Granite IRegion. 



The Granite Eegion is characterized hy a very different set of 

 palms. Where the rock is bare, or thinly covered with sand, the 

 whole vegetation is of that peculiar kind called '' Caa-tinga/' or 

 white forest, consisting of low thinly set trees and hushes, with 

 palms of singular aspect interspersed or gregarious in clumps or 

 patches. Tlie most notable Caatinga palms of the Granite are 

 Leopoldinia Piassaha, with its long brown beard reaching the 

 ground and giving half-grown trunks the appearance of bears ram- 

 pant, and Mauritia (^OropJioma) Carand^ whose crown of palmate 

 leaves rises over a huge mass of decaying persistent petioles. 



"Where the river-beds are of granite, as throughout this re- 

 gion they mostly are, only a very fcAV being in rifts or valleys 

 filled with alluvium, the phenomenon is seen of " aguas negras/' 

 or black-water streams, whose riparial vegetation is well charac- 

 terized by the abundance of two beautiful palms, both having 

 clustered or cespitose stems. One is the Mauritia aculeata of 

 Humboldt (' Ansichten der Natur/ i. 131), not the -3£ aculeata 

 of Martins, which is a distinct species with solitary stems, but 

 the same species as Wallace has figured under the name of -3£ 

 gracilis. It is a most graceful palm, the outer stems of each tuft 

 often leaning far over the water, and the fan-shaped leaves (blue- 

 green above, white beneath) having the laciniae pendulous from 

 the middle. In the other palm, Leopoldinia major (Wallace), 

 the leaflets of the pinnate leaves are pendulous from the very 

 base (as in the Euterpes), and the finely divided ferruginous 

 spadices bear blood-red flattened drupes. 



Two of the four palms above mentioned, Leopoldinia Piassaba 

 and major, seem nowhere to extend beyond the granite region ; 

 but I have traced the two Mauritias down to within thirty miles 

 of the mouth of the Eio Negro, on the small river Taruma, where 

 they grow in caatingas whose surface-sand reposes not on granite, 

 but on one of the harder layers of the Amazon sandstone*. 



* Similar conditions gave rise to the recurrence of "caatingas" throughout 

 the main Amazon ; but they are much rarer than on the Negro and Casiquiari, 

 and are sometimes replaced by scrubby savannahs, or "campos." All are 

 interposed in the vast primeval forest, and in a chmate of almost perpetual 



