The traveller into the interior hears many stories of great serpents and their doings; for instance, the story of the horned snake is famous all over South America, and while the details may vary, the main features are always the same. It is the tale of a person (usually the one telling the story) who came suddenly upon an enormous snake with a long horn on either side of the head. Of course, the reptile was immediately killed, sometimes with a rifle or revolver, or occasionally with a knife, after a desperate struggle. As the slain monster writhed its last, the heroic hunter made a startling discovery; the snake did not actually have horns; it had merely swallowed an ox, which feat it performed without difficulty until the head was reached; this refused to go down on account of the spreading horns lodging crosswise in the corners of the snake’s mouth. Hence the old, old story of the horned snake. Another favorite anecdote which I have heard repeated a number of times is that of the man who with his wagon, to which two oxen were hitched, attempted to ford a stream; suddenly an anaconda of enormous size emerged from the water and, enveloping both animals in its coils, crushed them to death. I never encouraged those telling this story to continue, because I was afraid that they might say the snake had swallowed both oxen and perhaps even the wagon at the same time! Not many years ago a South American explorer brought back photographs of the “trail” made by a huge snake in crawling along the sand. It would be easy to manufacture such a trail by dragging a bag full of sand along the ground, and while it is impossible to say that this was really done, such a photograph would be of no value, anyway, as it would be impossible to determine the size of the reptile from such a picture. In this way the evidence of the existence of gigantic snakes gradually dwindles away, and we are compelled to look for material on which we can lay our hands, whereon to base our knowledge. That is, the stories of the average traveller and native as well must not be taken too seriously; and only the skins or living specimens known to exist can be taken into consideration. The longest South American snake of which I could obtain any definite information is in a Brazilian museum, and was said to be about twenty-five feet long. A skin of this size may be stretched several feet during preparation, so the snake may have been somewhat shorter in life. In the Bronx Zoological Gardens, New York, there is a living anaconda fourteen feet long; the largest boa-constrictor is eleven feet in length.