Snakes: Curiosities and Wonders of Serpent Life

by Catherine Cooper Hopley

The keeper said, ‘No, the snake was not hurt. That he had often seen it like that when the snakes were feeding; and that he also thought it must be the windpipe, to enable the snake to breathe while feeding.’

Next day, with eager steps and excited curiosity, I hurried to the British Museum reading-room, thinking I had made a wonderful discovery, for I had never heard this strange phenomenon alluded to, and the keeper evidently knew very little about it.

With this great secret on my mind, I flew to the well-known shelves, to secure those books which would certainly enlighten me if information were to be had. Alas! for my wonderful discovery, though it really had been a portion of the windpipe which was thus extended from the mouth, it was what had been known long ago by those physiologists who had studied the anatomy of the ophidia, and it was as coolly described as if it were the commonest occurrence in the world for creatures to do what they pleased with their windpipe!

Says Professor Owen in his Anatomy of the Vertebrates, vol. i. p. 525: ‘The glottis of serpents can be drawn forward and protruded from the mouth by the action of’ (certain surrounding) ‘muscles. In marine serpents the glottis is situated very near the fore part of the mouth, and the air can be inspired at the surface of the water without exposure of the jaws.’

The lungs of snakes, then, are supplied with air through that moveable tube, and the ‘glottis,’ which is the mouth or opening of what may here be called the air-tube, not to venture on scientific terms, was what I had seen ‘puckered up,’ as it appeared.

We may briefly remind the reader that our own throats contain two passages, one to the lungs, the other to the stomach; and in order that the air passage may be safely guarded from the entrance of any foreign particles, there are various parts, valves, and muscles which come into play with the action of swallowing, each and all having technical names, larynx, pharynx, glottis, epiglottis, etc., which need not be here described. But in the adaptive development of those wonderful creatures, snakes, the entrance or mouth of the windpipe—which begins in their mouth—can not only be closed at will, but still further to protect the passage, and also to enable the reptiles to breathe during the long process of swallowing, they can absolutely bring the apparatus forward, even beyond their mouths; and this was what had so surprised me on witnessing it.

The glottis, being the soft, membranous end or aperture, was what opened and closed, expanded and contracted, by that sort of puckering up and loosening again that was observable, and which here was rounded, but in the higher animals is a narrow, lip-like slit.

Some physiologists, in describing this ‘air-tube’ of serpents, speak of it as the larynx, which is what we unscientific folk would call the entrance to, or the upper portion of, the true windpipe or trachea. Others, again, affirm that they saw the ‘windpipe’ projecting. After all, much less has been said about it than one could wish; and what is said is somewhat conflicting, perhaps on account of the obscurity connected with this surprising adaptation of means to necessities. A thorough examination of the position of the trachea of snakes while feeding, and a perfect realization of its functions, could only be obtained were it possible to arrest the process of feeding by the instantaneous death of the feeder, and while every muscle of the snake’s mouth remained in position. Even then, one could not be positive, as snakes are endowed with the astonishing power of carrying out their intentions, or, in common language, ‘going on with their business,’ even after death. That is to say, owing to the irritability of their muscles, the action which they were about to perform (as, for instance, springing at a foe) continues should the head be shot off at the moment of making the attempt. In p. 56 and chap. xxi. some remarkable elucidations of this are given.

The general appearance of a windpipe is familiar to every one. It is formed of a series of rings or hoops, partially cartilaginous in mammals; that is to say, they are incomplete behind, where their ends are united by muscle and membrane, and come in contact with the gullet; but in serpents the rings are entire, the ends of each being joined together by an elastic substance. The rings themselves are also connected with each other by elastic membranes, so that the windpipe is capable of being extended like an india-rubber tube, and of regaining its former position.