GEOGRAPHICAL DISTRIBUTION OF PLANTS. 541 
of wind was felt, as we rode upon our mules. Nevertheless, in the 
midst of this apparent calm, whirlwinds of dust. rose unceasingly, 
chased by little currents of air; which only skimmed the surface of 
the soil and raised the dust, giving birth to a difference of tempe- 
rature between naked sandy places and those covered with vege- 
tation, which rendered the former suffocating.” Through this atmo- 
sphere of quartz grains, dry fog, and banks of vapour, sometimes 
waving and sinuous, sometimes even-shaped, continues the learned 
traveller, “I saw naked trunks of palm-trees, destitute even of 
their crowning tuft of verdure. The trunks appear in the distance 
like the masts of ships on the horizon. There is something im- 
posing, but sad and melancholy, in the uniform appearance of these 
steppes. Everything appears immovable; the shadow of a little 
cloud, which sometimes traverses the zenith, announcing the ap- 
proach of the rainy season, is scarcely projected upon the savannah. 
The steppes are principally covered with graminaceous plants, such 
as Killengia, Cenchrus, and Paspalum. With these we find a few 
plants of the dicotyledonous class, such as the Turnera ; some 
Malvacee, and, what is very remarkable, the little Mimosa pudia, / 
with ieaves quite sensitive to the touch, which the Spaniards call 
Dornuderas. The same race of cows which in Spain fatten upon 
sainfoin and clover, here find excellent nourishment in the herba- 
ceous Sensitive plant. In the east, in the Llanos of Cairo and white 
Barcelona, the Cypura and Craniolaria, with their beautiful flowers, 
six to eight inches long, rise isolated among the graminaceous 
plants. The pasturage is fertile, not only near rivers subject to 
inundations, but also where the trunks of the palm-trees are most 
crowded, which is attributable to the shelter and protection which 
they give from the sun’s rays—which is the more remarkable, since 
the Palm of the Llanos (Corypha tectorum) has only very few cor- 
rugated and palmate leaves, like those of the Chamerops, the 
lower of which are always parched and dried up. Beside the 
isolated trunks of Palms we also find, here and there, in the Llanos, 
groups of Palms in which the Corypha mingles with a tree of the 
family of Proteacee—a new species of Rhopala, with hard and 
resonant leaves. In the Llanos of Caracas, the Corypha extends 
from the Mesade Paja to Guayaval. More to the north and north- 
west, it is replaced by another species of the same genus, with 
