8096 Marvels of the Universe 
limbs has disappeared long since, so that a careful examination would be necessary, for those who 
did not know the Slow-worm at sight, to decide whether it were a lizard orasnake. The distinguish- 
ing marks apart from coloration are not numerous. In the first place, the Slow-worm has a movable 
eyelid ; the true snake has no power of closing its eves, which are protected from injury by a trans- 
parent horny plate, like a watch-glass. Hence the stony stare of the snake that is so disconcerting. 
In the second, the Slow-worm has a slit marking the aperture of the ear, which is not found in the 
snake. Thirdly, the belly of the snake is provided with a series of horizontal plates which play 
an important part in locomotion. These are wanting in the Slow-worm. The Glass-snake, or 
Scheltopusik, of Southern Europe, is another of the lizards, which, in like manner, has lost its 
legs. In this snake the body bears along each side a deep groove, the purpose of which is not 
precisely known. Those who might desire further evidence as to former existence of legs in the 
Slow-worm would have to make a careful dissection, exposing the shoulder-girdle and hip-girdle, 
of which, at any rate, vestiges remain. In the Glass-snake small flaps of skin mark the last traces 
of the hind-legs ; the fore-legs have vanished utterly. 
But even after the examination I can imagine some being still rather doubtful as to the inter- 
THE GLASS-SNAKE. 
This is one of the most interesting of the American Lizards. It owes its name to the fragile jointing of the backbone, for 
the bones of the tail are so slightly linked together that it will break off at the slightest blow. This footless Lizard is therefore 
seldom captured without an injury. 
pretation of the evidence. Such will find all hesitation vanish, I imagine, after an examination of 
certain lizards known as skinks, wherein every gradation from the condition of four-leggedness to 
complete limblessness will be found. In the Biskran Skink both pairs of limbs are present, and 
each foot has five toes. It is, as may be seen in our illustration, a typical lizard. In the Atlas 
Mountain Skink the legs have all dwindled amazingly, the front limbs having become reduced to 
useless remnants ; yet all have four toes. In the Suakin Skink this process of degeneration has 
proceeded a stage further; and the fore-leg, now difficult to see, has still further reduced the 
number of its digits, only three remaining. But we have two stages further yet to go. The Three- 
fingered Skink has passed so far towards the limbless condition, that its legs are represented only by 
short, cylindrical stumps, cleft into three at the free end; digits these clefts can hardly be called, 
though they answer thereto. Finally we have Giinther’s Skink, wherein minute stumps, barely 
traceable in the living animal, and not at all in photographs, are all that remain of once 
functional five-fingered hands and feet. 
Only one other lizard need be mentioned in this connection, and this is the Scale-footed Lizard, 
wherein the fore-limbs have vanished completely, and all that remains of the hind-limbs is a pair 
of scale-like outgrowths. In all else, like the legless skink just referred to, the creature is, to the 
uninitiated, a snake—having, like the snakes, an excessively elongated body and no legs. 
