26 BULLETIN 1380, U. S. DEPARTMENT OF AGRICULTURE 
tions of the claret-colored and yellowish brown forms were not ob- 
served. The pubescent type was not seen on rubber in a fruiting 
condition. It was found fruiting on dead leaves and is referred to 
M. sarwventoms. 
BROWN SCALY BARK 
Sloughing of the outer bark on young trees averaging about 6 
inches in diameter was observed in low wet ground on the Rio Ouro 
Preto. The affected area included about half the diameter of the 
tree and extended about 2 feet above and below an apparent center 
of infection. At the upper margin there was a faint indication of 
a concentric arrangement of the dead bark scales, after the manner 
depicted and described by Keuchenius. The bark beneath the dead 
scales was generally healthy, but showed slightly brownish spots 
which did not produce latex when wounded. The rest of the 
affected area, which was slightly sunken below the general level and 
consequently not as thick as the normal bark, produced latex in 
abundance. The diseased bark, which was much darker than the 
normal, could be scraped away, leaving a brownish area conspicu- 
ous at a considerable distance. No organism was found. 
GRAY SCALY BARK 
At rare intervals in the vicinity of Para the stems of young trees 
from 2 to 3 inches in diameter near the surface of the ground bore 
ash-gray patches of irregular outline. The patches either extended 
completely around the stem or were in the form of elongated areas 
on one side. 
The general appearance was that of some of the numerous gray 
incrusting lichens, but when examined the patches were found to 
consist of a minute fine mycelium, ramifying in all directions around 
and beneath the small bark scales. There were no indications that 
this mycelium united to form threads, but under the lens it seemed 
to follow the fine breaks between the bark scales. The scales in the 
center of the patches could be lifted with the point of a needle, 
exposing this mycelium beneath. This apparent loosening of the 
small bark scales produced an easily perceptible roughening of the 
surface in the center of the patch and no doubt represented a more 
advanced development of the fungus, the mycelium at the edge of 
the patches thinning out until it could no longer be detected. These 
patches were not found on the branches of Hevea or on the leaves. 
Similar patches were also found on the smooth bark of young Inga, 
Cecropia, and cacao and in the same position, viz, about 8 to 10 
inches above the ground. In no case did these bark infections seem 
to have a pathogenic effect on the host. The cortex beneath ap- 
peared quite normal, and there was no discoloration. The phe- 
nomenon is one of the numerous epiphytic mycelial developments so 
common on bark surfaces in the Tropics and is of no consequence. 
Petch describes a " white stem blight " of Hevea and of tea which 
is parasitic on the leaves of the latter, and in some instances the 
cortex beneath the patches on Hevea is found to be brown, having 
separated from the wood. He describes the fungus as producing an 
effect as though the branches were whitewashed, due to the loosening 
of the small bark scales, forming small cords. The Amazon fungus 
did not produce cords, and the color appearance was gray. 
