IN THE CINCHONA FORESTS 281 
the other a beautiful arbuscle, seen only in the valley of San 
Antonio, where it grows from the very plain up to 2600 feet. 
The slender stems, of from 8 to 14 feet, are usually simple and 
arched, and the large white flowers grow in small pendulous 
corymbs from the axils of very large, elongate, glaucous leaves. . . . 
CrucifercB^ 2. — Apparently species of Sisymbrium, the one 
growing near streams, the other in open situations ; both in very 
small quantity. ... 
Capparidacece. — The only species observed was a Cleome, a 
genus which extends from the plain to a great height on the 
wooded hills. 
Sterculiacece. — A raft-wood tree, Ochroma, is pretty abundant. 
Another tree of the same order (not seen in flower) appears to be 
a Chorisia. 
Biittneriacece, i. — A rampant Melochia. Muntingia Calaburu^ 
a tree found in the plains on both sides of the Cordillera, grows 
abundantly by the Rio San Antonio, up to 2500 feet. 
MalvacecE, 2. — Four or five common weeds, whereof Sida 
glomerafa, Cav., is the most plentiful, comprise all that was seen 
of this order. 
TiliacecE, 1. — A very handsome tree, with a slender straight 
trunk, reaching 60 feet, very long branches, large, ligulate, serrated, 
distichous leaves, and terminal panicles (sometimes 4 feet long) 
of yellow flowers, scented like those of Tilia EuropcEa ; it is 
abundant and ornamental about the middle region of the Red 
Bark. Besides this tree, another of the same order (apparently 
a Heliocarpus), growing to about 30 feet, is also frequent. . . . 
PolygalecE^ 2. — A Monnina and Polygala paniculata^ L. . . . 
The Polygala of the Bark woods is the common and almost the 
only species of the equatorial Andes, on whose western slopes it 
descends to the plain, and does not seem to ascend higher than 7000 
feet on either side, nor is it abundant at any elevation. When 
I recollect the abundance of Polygala vulgaris on cold English 
moors, I am struck with this paucity of Polygalse in the Andes, 
and still more when I compare it with their abundance and 
variety on hot savannas of the Orinoco, and in hollows of 
granite rocks by the Atabapo. 
SapindacecE^ i. — A woody climbing Serjania, a fine plant. 
A Paullinia with trigonous stems is frequent, and is the common 
substitute for rope, where much strength is not required. I saw 
no flowers of it, and only empty capsules. There is also a 
Cardiospermum, which I have seen on both sides of the Cordillera 
up to 7500 feet, and this is the greatest elevation at which I have 
noted any Sapindacea, an order which abounds in the hot plains. 
Malpighiacece^ i. — A twiner, with fruit too young to enable 
me to speak positively of the genus. Plants of this order, which 
constitute so large a proportion of the vegetation of the plains, 
