The early morning was always lovely on these rivers, and at that hour many birds and beasts were to be seen.  One morning we saw a fine marsh buck, holding his head aloft as he stared at us, his red coat vivid against the green marsh.  Another of these marsh-deer swam the river ahead of us; I shot at it as it landed, and ought to have got it, but did not.  As always with these marsh-deer—­and as with so many other deer—­I was struck by the revealing or advertising quality of its red coloration; there was nothing in its normal surroundings with which this coloration harmonized; so far as it had any effect whatever it was always a revealing and not a concealing effect.  When the animal fled the black of the erect tail was an additional revealing mark, although not of such startlingly advertising quality as the flag of the whitetail.  The whitetail, in one of its forms, and with the ordinary whitetail custom of displaying the white flag as it runs, is found in the immediate neighborhood of the swamp-deer.  It has the same foes.  Evidently it is of no survival consequence whether the running deer displays a white or a black flag.  Any competent observer of big game must be struck by the fact that in the great majority of the species the coloration is not concealing, and that in many it has a highly revealing quality.  Moreover, if the spotted or striped young represent the ancestral coloration, and if, as seems probable, the spots and stripes have, on the whole, some slight concealing value, it is evident that in the life history of most of these large mammals, both among those that prey and those that are preyed on, concealing coloration has not been a survival factor; throughout the ages during which they have survived they have gradually lost whatever of concealing coloration they may once have had—­if any—­and have developed a coloration which under present conditions has no concealing and perhaps even has a revealing quality, and which in all probability never would have had a concealing value in any “environmental complex” in which the species as a whole lived during its ancestral development.  Indeed, it seems astonishing, when one observes these big beasts—­and big waders and other water-birds—­in their native surroundings, to find how utterly non-harmful their often strikingly revealing coloration is.  Evidently the various other survival factors, such as habit, and in many cases cover, etc., are of such overmastering importance that the coloration is generally of no consequence whatever, one way or the other, and is only very rarely a factor of any serious weight.

The junction of the Sao Lourenco and the Paraguay is a day’s journey above Corumba.  From Corumba there is a regular service by shallow steamers to Cuyaba, at the head of one fork, and to Sao Luis de Caceres, at the head of the other.  The steamers are not powerful and the voyage to each little city takes a week.  There are other forks that are navigable.  Above Cuyaba and Caceres launches go