Snakes: Curiosities and Wonders of Serpent Life

by Catherine Cooper Hopley

Bearing in mind that each of these highly complicated joints supports a pair of moveable ribs, and that the ends of these ribs are connected by muscles with the large stiff scutes or scales crossing the under surface of the body (see illustrations, p. 193), which move with the ribs, one foot-like scale to each pair, we comprehend how snakes exceed millipedes in the number of their limbs, if not true legs, and how they excel the insect also in variety of movement. Those ‘ball and socket’ joints admit of free lateral flexion, and every variety of curvature—‘the utmost pliancy of motion,’ to repeat the words of Rymer Jones; and also of that surprisingly independent motion which enables the constrictors to surpass even the Bimana (except practised experts) in doing several things at once.

Thoughtful persons who can contemplate this wondrous organization with due reverence, and witness it in activity—as we admiringly observe the works of a watch in motion—will forget to censure those who supply food to this piece of animated mechanism, and even pardon a hungry little snake for so expertly securing three birds at once.

Think of 300 back-bones and 300 pairs of legs, all requiring wholesome exercise. Some snakes have 300 pairs of ribs—each pair capable of independent motion, and articulated with that complex spine; and each pair moving together, and carrying along with them a foot in the shape of a broad ventral scale. ‘This scutum by its posterior edge lays hold of the ground,’ says Sir Everard Home, ‘and becomes a fixed point whence to set out anew.’

The hold which the ventral scales have of the ground obviously renders it easier for the reptiles to pass over a rough than a smooth surface; what are obstacles to other creatures are facilities to them. But they appear to be never at a loss. On a boarded room, or even a marble floor, they will manage progression of some sort,—many by the pressure of the tail to push themselves forward, and others with an action that can be compared only with swimming. With the same rapid, undulating motion as swimming, the active snakes skim through the grass, or over soft herbage, on which they seem to make no impression. Their swift sinuations are almost invisible to the eye. You only know that a snake was there, and now has vanished. The ‘Rat’ snake of Ceylon (Ptyas mucosus) (see frontispiece) and the ‘Pilot’ snakes of America are among the best known of these swift-flitting or gliding creatures.

Rats are fleet little quadrupeds, but their enemies, the Rat snakes of India, are more than their match. Sir Emerson Tennant, in his History of Ceylon, describes an encounter with one. Ptyas mucosus caught a rat, and both captor and captive were promptly covered with a glass shade to be watched. With an instinct to escape stronger than hunger, Ptyas relinquished his hold, and manifested uneasiness. Then the glass shade was raised a trifle, and instantly away ran the rat; but the snake was after it like a flash, caught it, and glided away swiftly, with head erect and the rat in its mouth.

At one of the Davis lectures at the Zoological Gardens, a fine Rat snake in the Society’s collection was exhibited, and was permitted to be handled by a favoured few. To hold it still was not possible, for the creature glided through the hand, and entwined itself about one as if a dozen snakes had you in possession. It was very tame, and accustomed to be handled by the keeper, whose especial pet it was; otherwise Ptyas is a powerful snake, and quite capable of strangling you should it take a fancy to constrict your neck. On another occasion this same snake constricted my arm sufficiently to make my fingers swell; but that was not so much in anger as for safety, because it did not like to be fettered in its movements, or to be somewhat unceremoniously examined. A younger and less tame specimen tried to bite me, and squeezed my fingers blue by constricting them.

There is no circumventing these ‘lithe and elegant beings.’ They will get into your pocket, or up your sleeve; and while you think you have the head safely in your hand, the whole twelve feet of snake will have glided through, and be making its way to the book shelves, or where you least expect to see it.

When frequently handling the young constrictors, one has been able to feel as well as to observe the action of the ribs. As they pass through the hand, you feel them expanded, so as to present a flatter under surface. In Ptyas the back is remarkably keeled when crawling, a section of his body presenting the form of the middle diagram given below.