in such manner as to escape observation approach more or
less closely to the ideal which the cats most nearly realize.
Wariness, sharp senses, the habit of being rigidly motionless when
there is the least suspicion of danger, and ability to take advantage
of cover, all count. On the bare, open, treeless plain, whether marsh,
meadow, or upland, anything above the level of the grass is seen at
once. A marsh-deer out in the open makes no effort to avoid
observation; its concern is purely to see its foes in time to leave a
dangerous neighborhood. The deer of the neighboring forest skulk and
hide and lie still in dense cover to avoid being seen. The white-
lipped peccaries make no effort to escape observation by being either
noiseless or motionless; they trust for defence to their
gregariousness and truculence. The collared peccary also trusts to its
truculence, but seeks refuge in a hole where it can face any opponent
with its formidable biting apparatus. As for the giant tamandua, in
spite of its fighting prowess I am wholly unable to understand how
such a slow and clumsy beast has been able through the ages to exist
and thrive surrounded by jaguars and pumas. Speaking generally, the
animals that seek to escape observation trust primarily to smell to
discover their foes or their prey, and see whatever moves and do not
see whatever is motionless.

By the morning of January 5 we had left the marsh region. There were
low hills here and there, and the land was covered with dense forest.
From time to time we passed little clearings with palm-thatched
houses. We were approaching Caceres, where the easiest part of our
trip would end. We had lived in much comfort on the little steamer.
The food was plentiful and the cooking good. At night we slept on deck
in cots or hammocks. The mosquitoes were rarely troublesome, although
in the daytime we were sometimes bothered by numbers of biting horse-
flies. The bird life was wonderful. One of the characteristic sights
we were always seeing was that of a number of heads and necks of
cormorants and snake-birds, without any bodies, projecting above
water, and disappearing as the steamer approached. Skimmers and thick-
billed tern were plentiful here right in the heart of the continent.
In addition to the spurred lapwing, characteristic and most
interesting resident of most of South America, we found tiny red-
legged plover which also breed and are at home in the tropics. The
contrasts in h