Cuap. VII. FOREST AROUND BARRA. 175 
species not found on the margins of the Amazons, which has a scanty 
head of fronds, with narrow leaflets of the same dark green hue as the 
rest of the forest. The stem is smooth, and about two inches in 
diameter ; its height is not more than twelve to fifteen feet ; it does not, 
therefore, rise amongst the masses of foliage of the exogenous trees, so 
as to form a feature in the landscape, like the broad-leaved Muru-murti 
and Urucuri, the slender Assai, the tall Jauarf, and the fan-leaved 
Muruti of the banks of the Amazons. On the shores of the main river 
the mass of the forest is composed, besides palms, of Leguminosz, or 
trees of the bean family, in endless variety as to height, shape of 
foliage, flowers, and fruit ; of silk-cotton trees, colossal nut-trees (Lecy- 
thidez), and Cecropiz ; the underwood and water-frontage consisting 
in great part of broad-leaved Musacez, Marantacez, and succulent 
grasses, all of which are of light shades of green. The forests of the 
Rio Negro are almost destitute of these large-leaved plants and grasses, 
which give so rich an appearance to the vegetation wherever they grow ; 
the margins of the stream being clothed with bushes or low trees, 
having the same gloomy monotonous aspect as the mangroves of the 
shores of creeks near the Atlantic. The uniformly small but elegantly 
leaved exogenous trees, which constitute the mass of the forest, consist 
in great part of members of the Laurel, Myrtle, Bignoniaceous, and 
Rubiaceous orders. The soil is generally a stiff loam, whose chief 
component part is the Tabatinga clay, which also forms low cliffs on the 
coast in some places, where it overlies strata of coarse sandstone. ‘This 
kind of soil, and the same geological formation prevail, as we have seen, 
in many places on the banks of the Amazons, so that the great contrast 
in the forest clothing of the two rivers cannot arise from this cause. 
I did not stay long enough at Barra to make a large collection of the 
animal productions of the neighbourhood. I obtained one species of 
monkey ; not more than a dozen birds, and about three hundred species 
of insects. Judging from these materials, the Fauna appears to have 
much in common with that of the sea-coast of Guiana; but, at the same 
time, it contains a considerable number of species not hitherto found 
in Guiana, or in any other part of South America. The resemblance 
between the eastern shore of the Rio Negro and the distant coast of 
Guiana, in this respect, appears to be greater than that between the Rio 
Negro and the banks of the Upper Amazons.* 
The species of monkey mentioned above was rather common in the 
forest ; it is the Midas bicolor of Spix, a kind I had not before met 
with, and peculiar, as far as at present known, to the eastern bank of 
the Rio Negro. The colour is brown, with the neck and arms white. 
* My own material is perhaps not sufficient to establish this view of the relations 
of the Fauna, for it requires the comparison of an extensive series of species to obtain 
sound results on such subjects. A few conspicuous instances, however, pointed to the 
conclusion above mentioned. For example: in birds, the beautiful seven-coloured 
Tanager, Calliste tatao, the ‘‘ sete cores ” of the Brazilians, a Cayenne bird, is common 
to Guiana and the neighbourhood of Barra, but does not range farther westward to 
the banks of the Solimoens ; where, from Ega to Tabatinga, the allied form of 
Calliste Yeni takes its place. The Ramphastos Toco, or Tocano pacova (so named 
from its beak resembling a banana or pacova), a well-known Guianian bird, is found 
also at Barra, but not farther west at Ega. In Coleopterous insects such species as 
