One of the most experienced collectors, M. Oversluys, writes from the Rio de Yanayacca, January, 1893:—

"Here it is absolutely necessary that one goes himself into the woods ahead of the peons, who are quite cowards to enter the woods; and not altogether without reason, for the larger part of them get sick here, and it is very hard to enter—nearly impenetrable and full of insects, which make fresh-coming people to get cracked and mad. I have from the wrist down not a place to put in a shilling piece which is not a wound, through the very small red spider and other insects. Also my people are the same. Of the five men I took out, two have got fever already, and one ran back. To-morrow I expect other peons, but not a single one from Mengobamba. It is a trouble to get men who will come into the woods, and I cannot have more than eight or ten to work with, because when I............