Skeleton of Lizard.

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The limbs of the Lizards agree structurally with those of the Mammals, each ending in a well-formed hand or foot with five long and slender digits, each with a curved claw—those of the hand worn short and blunt by their use in scraping the earth.

Their principal food is furnished by the various tribes of insects—flies, beetles, moths, and caterpillars, though spiders are greatly appreciated. Unless they are very small, caterpillars do not appear to be swallowed, but rather chewed and the skin rejected. The name vivipara refers to the fact that the female retains her eggs until they are fully developed and ready to hatch, so that the young are born free from the egg-membrane, or the egg breaks in the act of oviposition or immediately after. They are deposited anywhere: there is neither nest nor concealment, and the mother exhibits no interest or concern in her progeny. These number from six to twelve, and are nearly black. They remain motionless where they were born for several days. They are about an inch long. They start life so well nourished that they take no food for several days, then start hunting for small insects, such as Aphides and other soft-bodied species. The teeth are very small and conical, and unfitted to deal with hard substances; and as the two halves of the lower jaw are firmly connected there can be no distension of the small mouth to accommodate large parcels of food, as happens with the Snakes.

Points to be noted in the external appearance of the Common Lizard, when we have succeeded in capturing one, are the fact that the entire body is clothed with smooth, slightly keeled, and scarcely overlapping scales, small on the upper side, excepting the head, where they are large. On the underside, too, they are larger, especially from the breast to the vent, where they become broad plates, of which there are six rows, the two central rows being much smaller than the lateral ones. A row of larger scales forms a sort of collar across the underside of the neck. The Lizards have not that fixed, ever-open-eyed stare of the Snakes. The Lizard can follow your movements with his eye, and wink at you intelligently, because he is provided with eyelids, which the Snake lacks. He closes his eyes in sleep. When he puts out his tongue to ascertain whether an insect is good for food, you will notice that the broad tip of it is notched into two rounded lobes, instead of being forked into two thread-like points, as in the snakes. The usual attitude of the Common Lizard is with the extended tail and greater part of the body resting on the ground, or other support, whilst the head and foreparts are raised on the arms, and the muzzle turned to one side in an attitude that suggests listening. It has been stated that Lizards are susceptible to musical sounds, and that they may be attracted from their hiding-places by judicious whistling.

[Pl. 86.]][K 138.
Sand Lizard female.
Lacerta agilis.