The food of the Slow-worm is governed by the small size of the mouth. It is not an easy matter to study its feeding habits when it is at large, and our knowledge of its food preferences have been derived mainly from Slow-worms in captivity. It will take spiders, small earthworms, and small insects; but always shows a marked preference for the small greyish-white slug (Limax agrestis) that is so great a pest to the grower of tender vegetables. This slug the Slow-worm consumes in quantity. Dr. Gerald Leighton, in his book on the "British Lizards," says: "I can vouch for a meal that consisted of seventeen slugs, the Slow-worm being a large male sixteen inches long. But the usual number taken seems to be from four to ten." Its principal feeding time is soon after sunset, when the slugs are most in evidence on the surface and beginning to make their nefarious attacks on the food of man. If the gardener, professional and amateur, could only be taught such facts, the sudden descent of the sharp edge of spade or hoe upon one of his ablest helpers might be stayed. The reptiles and the batrachians are all his friends.

Like the Common Lizard, the female Slow-worm retains her eggs until they are fully developed, so that in August or September she produces a litter of six to twelve animated silver needles about two inches in length, with a thin black line along the centre of the back, and black on the underside. These are very active and very beautiful, perfectly independent and able to fend for themselves, catching insects, but at once showing preference for slugs if these are to be found of a size small enough to pass the tiny mouth. There is a record of a batch that were three inches in length at birth, but this is unusual. Occasionally the eggs are deposited before hatching.

Although in early spring the Slow-worm may be seen along hedgerows frequently in the daytime, later in the year it must be sought in the dusk when it is food-finding. It then spends the day under flat stones and in burrows. In Cornwall years ago we could always find a number of Slow-worms by turning over such loose stones along the top of the cliffs; and we have since found them pretty generally distributed without much regard to the nature of the soil. Its principal enemies—besides man—are the Viper and the Hedgehog. In the winter the Slow-worm retires—often in the company of half a dozen or so of its own kind—into an underground burrow or a hollow beneath a large stone, and goes to sleep; but it is the first of the reptiles to reappear at the very beginning of spring. Like its congeners it casts its skin from time to time—apparently about four times a year, but the frequency of the sloughing depends, of course, upon whether it is a good slug year or the reverse, for the shedding of the cuticle is in response to the demand for more room for the growing body. The Slow-worm's length of life is not known; but it does not appear to attain to sexual maturity until it is four or five years of age. We have reliable knowledge of one that was captured when about a foot in length (probably five or six years old), fifteen years ago, which is still healthy and active.

[Pl. 90.]][K 144.
Slow-worm.
Anguis fragilis.

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[Pl. 91A.]]
Grass Snake casts its skin.
1. Immediately before sloughing.