First let us briefly review her many wrong names, ‘blindworm,’ ‘slow-worm,’ ‘deaf-adder,’ ‘brittle-snake,’ and endeavour to account for them. Of her name ‘snake’ (Anguis), from its external aspect, enough has already been said. The ‘brittleness’ shared in common with several of her foreign relatives, known as ‘glass snakes,’ proceeds from a power of contracting the muscles into rigidity when molested: that is, when, on finding themselves in a helpless condition, slow-worms grasp firmly whatever they can attach themselves to. In fact, this little snake only displays constricting powers as far as it is able; for it really does constrict the fingers which detain it, with a force as great for its size as its cousin Anaconda uses in killing its prey. Were the giant constrictors to entwine us with proportionate power, they would gain the day. In the case of Anguis fragilis, we are the masters; and were we to attempt violently to unwind one from our fingers, it would break ‘in halves’ in its resistance, or rather in its redoubled efforts to cling the tighter and so save itself. May it not in this respect, also, claim kinship with its giant rivals, and show their common ancestry? On pp. 183 and 187 reference was made to the ‘blindworm’ in connection with other ‘brittle’ snakes, and in the use of their pointed tails. Our native ‘blindworm,’ in not having the hard point at the end, has escaped the imputation of trying to ‘sting’ with that imaginary weapon, although it uses its tail with equal and similar force, and for the same purpose. In handling the little reptile, you will feel it pressing the tip of its tail against whatever part comes in contact with it, as a hold, a fulcrum, and motive power.
Lizzie; never at a loss.
Upon a smooth surface it would be entirely helpless without this assistant to progression, its scales being too even and polished to afford hold of any kind. You will see it sweeping its long tail this way and that, in search of some hold or obstacle against which to push itself forward; and failing this, the point is pressed close to the table or floor as may be. When in any unaccustomed position, as, for instance, when held in the hand, you will see the tail instantly twining itself about the fingers for safety, the creature trusting itself entirely to its aid, and being helpless when its movements are fettered in any way. If not strictly prehensile in the way of affording support, as the tail of a true boa does, that of Anguis fragilis is not far removed from it. Hold one that is accustomed to be handled and in good health, and permit it to hang by the mere tip, as in the accompanying illustration. So far from falling, the little creature will at once draw itself upwards and backwards with perfect facility, till it feels itself equally balanced, when the tail will be sent in search of hold; it will cling quickly round a finger, and then Anguis feels itself safe once more. My tame slow-worms accomplished this with perfect ease whenever so suspended.
Others, unaccustomed to such a position, or in a not very robust condition, must be treated cautiously under this experiment, and not permitted to fall; but in every case the tail will be seen to be a very important agent to the reptile. It is longer in the male than in the female slow-worm—more than half the entire length in the former, and less than half in the latter. The males are, therefore, longer on the whole, though the body itself is longest in the female. Regard should be had to this, when, roughly speaking, they are said to ‘break themselves in halves;’ because it is not the body which breaks, but only the tail, or a portion of it, in common with other lizards.
The power of the tail in this reptile was again seen when its home was a bell-glass, such as is used for gold-fish. The one in which my first family of slow-worms dwelt, was almost as high as their own length, so that I considered them sufficiently secure without any cover to it. But after a little while they effected an exit. How, was at first a mystery, until I saw them perseveringly raising themselves in a perpendicular direction against the side. Many a slip and many a trial had they, but they rarely desisted until success crowned their efforts. When their head had once gained the edge of the glass, they easily drew themselves up and over it, and let themselves down on the outside, as you would draw a cord over the edge. The perfect smoothness of the glass, the nice balance required, and the gradual lowering of themselves, rendered this proceeding still more astonishing; for as the glass was on a stand there was a considerable distance between the edge and the table. A slow-worm’s progression is truly marvellous. In this little creature one can detect no action of the ribs; they are too fine and too close. Its scaly armour, moreover, is smooth and firm; and as for ventral scutæ to ‘afford hold,’ it has none. Yet with ease it draws itself over that polished rim, as it draws itself up and over your finger, when suspended by the mere tip of its tail.
Soon the slow-worms accomplished this feat so knowingly that it became necessary to cover them over, which was done with gauze having a strong elastic cord hemmed into it. They practised their climbing powers all the same, and though not able to get over the edge, tried and pushed hard enough to stretch the gauze considerably; so that, unless well pulled down, it lay only loosely and bagging over the top.
Judge, then, of my amazement one day to find Lizzie outside the glass, resting contentedly in the loose fold round the edge above the elastic. The little creature had absolutely got over the edge, but the tightness of the elastic baffling the outside descent, there it lay.