Unfortunately, the position of the tanks in the cages at the London Zoological Gardens, and the stone ledge in front of them, prevent the visitors from watching the actions of the snakes in the water, either when swimming or drinking. Occasionally one of the inmates of the larger cages may be seen in a pan of water, though their motions are necessarily restricted there. One day, however, the yellow Jamaica boa, when drinking from the pan, afforded an excellent opportunity for observation. And he was a long time imbibing. There was no perceptible action of the lips, which were barely parted. The snake kept its mouth just below the level of the water, and the only action or movement seen was at the back of the head, or on each side of the neck, like a pulsation, as the water passed down in short gulps. This is the ‘suction’ which writers describe, a drawing in of the liquid; but the lips do not take part in the act. When, therefore, we read that snakes drink both by lapping and also by suction, we may surmise that the former is for the benefit of the tongue, the latter of the body; and a large quantity of liquid is often drawn in by this sort of suction, very distinct from ‘sucking,’ the reputed way of enjoying milk from the living fountain, and a process impossible to creatures that have not soft lips and a broad tongue. The Jamaica boa drew in those perceptible gulps for a long time, then raised his head, and rested awhile, and presently drank again, and this several times while we were watching. It was what Dumeril described _à la régalade_. Mr. Sam Lockwood of New Jersey, writing in the _American Naturalist_, vol. ix. 1875, describes the pine snake drinking. ‘It lays its head flat upon the water, letting the lower jaw just sink a little below the surface, when with a very uniform movement the water is drawn up into the mouth and passed into the throat. It is true drinking, like that of a horse.’ One that he watched drank five minutes by the clock without taking breath. Then it paused, looked about for three minutes, and then drank again for five minutes more. ‘In all, it drank a little over a gill. Previously it has been without water for four weeks.’ In size this pine snake differs not much from the Jamaica boa (_Chilobothrus inornatus_), that we watched at the Gardens, and the manner and time were very similar. True, we did not time him by a watch, nor could we tell exactly how much he drank, nor how long previously he had been without drinking; but, at a guess, he could not have been much less than five minutes without taking breath. _Anguis fragilis_, that lapped seventy times, and stopped, and lapped again, must also have been some minutes without breathing, because hers was the most leisurely lapping I ever saw. [Illustration] CHAPTER V. _THE TONGUE OF A SNAKE._ PART I.—WHAT IT IS _NOT_.