284 BOTANICAL INFORMATION. r 
plenty of Podostemons on the granite rocks which peep out of the river 
(and, by the bye, make the navigation very dangerous), but all, al? 
dead and burnt up. It is here as I remarked at Santarem—the Podo- 
stemons flower just as the water leaves them, that is, early in the dry 
season, and my ascent of the Rio Negro was made towards the close of 
the dry season ; but if I live these little fellows shall not escape me. 
As their fruit is exposed to a burning sun six months or more in the 
year, I do not see why they should not travel safely to England in a 
letter, and I accordingly enclose capsules of one of the largest species. 
They ought to vegetate on stones (especially granite) barely emersed 
from the water of a tank; though here they never grow in stil? water ; 
always in rapids or cataracts where the water rushes over them. 
I had sad news two days ago from my friend Wallace: he is at Saû 
Joaquim, at the mouth of the Uauapés, a little above S. Gabriel, and he 
writes me by another hand that he is almost at the point of death, 
from a malignant fever, which has reduced him to such a state of weak- 
ness that he cannot rise from his hammock nor even feed himself. The 
person who brought me the letter told me that he had taken no 
nourishment for some days, except the juice of oranges and cashews. 
Since I came to Pará the fevers of the Rio Negro have proved fatal to 
two of the persons mentioned in Edwards’s Voyage—Bradley and Ber- 
chenbrinck, very fine young men both.  Wallace's younger brother, 
who came out from Liverpool along with me, died last May in Para; 
he had gone there, poor fellow, to embark for England—took the yellow 
fever, and died in a few days. 
The Rio Negro might be called the Dead River: I never saw such à 
deserted region ; in S. Isabel and Castanheiro there was not a soul as I 
came up, and three towns marked on the most modern map I possess 
have altogether disappeared from the face of the earth. We had beau- 
tiful weather in coming up, and to this may be attributed that I and all 
my people arrived here in good health. The region of malaria ends 
at Castanheiro, but the poison is said to remain in the system some- 
times thirty days before it shows itself, so that I am told to consider 
myself not yet out of danger. I do not however let this in the least 
annoy me: I am not one of the forwardest to face perils, but once em- 
barked I think no more of consequences. Mr. Wallace came up from 
the Barra more than a month before me, escaped the Sezoëns on his 
way, but the day he set foot in Saó Joaquim he was attacked. 
