Cuap. VIII. BRAZIL NUT TREES. 203 
geologist sufficient to pronounce on such questions. Mr. Wallace states 
that he found fragments of scorize, and believes the hill to be a volcanic 
cone. To the south and east of this isolated peak, the elongated ridges 
or table-topped hills attain a somewhat greater elevation. 
The forest in the valley is limited to a tract a few hundred yards in 
width on each side the different streams: in places where these run 
along the bases of the hills, the hill-sides facing the water are also richly 
wooded, although their opposite declivities are bare or nearly so. The 
trees are lofty and of great variety ; amongst them are colossal examples 
of the Brazil nut tree (Bertholletia excelsa), and the Pikid. This latter 
bears a large eatable fruit, curious in having a hollow chamber between 
the pulp and the kernel, beset with hard spines, which produce serious 
wounds if they enter the skin. The eatable part appeared to me not 
much more palatable than a raw potato; but the inhabitants of Santarem 
are very fond of it, and undertake the most toilsome journeys on foot to 
gather a basketful. The tree which yields the tonka bean (Dipteryx 
odorata), used in Europe for scenting snuff, is also of frequent occurrence 
here. It grows to an immense height, and the fruit, which, although a 
legume, is of a rounded shape, and has but one seed, can be gathered 
only when it falls to the ground. A considerable quantity (from 1000 
to 3000 pounds) is exported annually from Santarem, the produce of the 
whole region of the Tapajos. An endless diversity of trees and shrubs, 
some beautiful in flower and foliage, others bearing curious fruits, grow 
in this matted wilderness. It would be tedious to enumerate many of 
them. I was much struck with the variety of trees with large and 
diversely-shaped fruits growing out of the trunk and branches, some 
within a few inches of the ground, like the cacao. Most of them are 
called by the natives Cupu, and the trees are of inconsiderable height. 
One of them, called Cupt-ai, bears a fruit of elliptical shape and ofa 
dingy earthen colour, six or seven inches long, the shell of which is 
woody and thin, and contains a small number of seeds loosely en- 
veloped in a juicy pulp of very pleasant flavour. The fruits hang like 
clayey ants’-nests from the branches. Another kind more nearly re- 
sembles the cacao ; this is shaped something like the cucumber, and has a 
green ribbed husk. It bears the name of Cacao de macaco, or monkey’s 
chocolate, but the seeds are smaller than those of the common cacao. 
I tried once or twice to make chocolate from them. They contain plenty 
of oil of similar fragrance to that of the ordinary cacao-nut, and make 
up very well into paste; but the beverage has a repulsive clayey colour 
and an inferior flavour. 
My excursions to the Irurd had always a picnic character. A few 
rude huts are scattered through the valley, but they are tenanted only 
for a few days in the year, when their owners come to gather and roast 
the mandioca of their small clearings. We used generally to take with 
us two boys—one negro, the other Indian—to carry our provisions for 
the day: a few pounds of beef or fried fish, farinha and bananas, with 
plates, and a kettle for cooking. José carried the guns, ammunition, 
and game-bags, and I the apparatus for entomologising—the insect net, 
a large leathern bag with compartments for corked boxes, phials, glass 
tubes and so forth. It was our custom to start soon after sunrise, when 
