A young python was hanging from a branch, more than half its body curved as in the accompanying sketch, remaining motionless and quiescent, watching some sparrows which the keeper had just put into the cage. The birds, eyeing certain insects among the gravel, seemed all unconscious of the pair of glistening eyes looking down upon them. Suddenly a movement, a flicker, like the flash of a whip, and the snake had changed its position. Too quick for us to follow the motion, but in that flash of time it now hung like a pendulum, with a sparrow almost hidden in its coils. The snake had precisely measured its distance, reached down, and recoiled with the swiftness of an elastic spring. After a few minutes, _feeling_ that its prey was dead, it prepared to swallow it, holding it encircled in a portion of its body, while the head was free to commence the usual examination. Still hanging there, it held and devoured the bird. On another occasion, one of the larger pythons caught a guinea-pig in the same manner. This also was so quick in its movements that one scarcely knew what had happened until the snake was seen to have changed its position, some of the anterior coils had embraced a something, and a quadruped was missing. This snake also still hung while eating its meal, the whole process occupying less than ten minutes. In both these cases we saw the prehensile tail in its natural use, while the rest of the body was free for action. One of the most remarkable cases of what we may call independent constricting powers, that is, two or more parts of the reptile being engaged at the same time, was in some very hungry, or very greedy, or very sagacious little constrictors, the ‘four-rayed snakes,’ _Elaphis quater-radiatus_.