43 
WONDERS OF THE TROPICAL FORESTS, 
wMle tbe melon-sliaped Echinocacti and Mammillarias, 
longitndinally ribbed or covered witb warts, nemam attached 
to the soil- The dimenBioiis of theso monstrous phints 
are exceeciin*^ly variable. One of tbe Mexican ecbinoeacti 
measures four feet in height, three in diameter, and weighs 
about two hundred pounds ; while the dwarf cactus is so 
araali that, loosely rooted in the sand, it frequently remains 
sticking between tbe toes of the doga that pass over it. 
The splendidly coloured llowers of the cactuses form a 
strange contrast to the deformity of their stems, and the 
spectator stands astonished at the glowing lifo that springs 
forth from so unpromising a stock. These strange com- 
pounds of ugliness and beauty are in many respects use- 
fill to man. The pulp of the melocacti, which remains 
juicy during the driest season of the yenr, is one of the 
vegetable sources of the wilderness, and refreshes the 
traveller after he has carefully removed tbe thorns. 
Almost all of them bear an agreeable acid fruit, which, 
under the name of tbe Indian fig, is consumed in large 
quantities in the West Indies and Mexico. Tlie light and 
incorruptible wood is admirably adapted for tbe construc- 
tion of oars and many other implements. The farmer 
fences bis garden with the prickly opuntias; but the 
services which they render, as the plants on which the 
valuable cochineal insect feeds and multiplies, are far more 
important. 
The cactuses prefer the most arid situation, naked plains, 
or slopes, where they are fully exposed to the burning 
rays of the sun, and impart a peculiar physiognomy to a 
great part of tropical America. 
None of the plants belonging to this family existed in 
the Old World previous to the discovery of America ; 
but some species have since then rapidly spread over the 
warmer regions of our hemisphere. The Nopal skirts the 
Mediterranean along with the American agave, and from the 
coasts has even penetrated far into the interior of lifrica, 
everywhere maintaining its ground, and conspicuously 
