Occipital plate rudimentary; frontal large, as broad behind as before: temples covered with small plates: abdominal lamellae in six rows: fore feet with the fourth toe longest: femoral pores from nine to eleven.
* Nat. Hist. of Selbnrne: seventeenth letter to Mr. Pennant.
L. agilis, Berkenh. Syn. vol. i. p. 56. Sheppard in Linn. Trans. vol. vn. p. 49. Turt. Brit. Faun. p. 79. Flem. Brit. An. p. 150. Scaly Lizard, Penn. Brit. Zool. vol. in. p. 21. pl. 2. no. 7.
Entire length from six inches to six inches nine lines. Relative proportions very variable.
(Form). In every respect smaller, and more slender, than the L. Stirpium: snout rather sharper: head more depressed, with the superciliary plates raised above the level of the crown: occipital plate very small; frontal large, as broad at its posterior as at its anterior margin: temples covered with small plates, more numerous than in L. Stirpium: collar composed of nine nearly equal lamellae, with the posterior margin entire: pectoral triangle ill-defined, the lamellae crowded together in an irregular manner: abdominal lamellae in six longitudinal rows; the two middle rows a little narrower than the adjoining ones, with the lamellae in these rows approaching to square or rectangular: dorsal scales rather narrower than in the L. Stirpium; not carinated, or with the keel very obsolete: caudal scales similar, but the keel of these also less strongly marked; the terminal point of each scale is likewise more obtuse, causing the whorls to appear less crenated: feet much slenderer than in the above species; the fore feet with the fourth toe a little longer than the third; claws small, and not more developed before than behind: thighs scarcely compressed; the number of femoral pores tolerably constant, generally nine, sometimes ten, rarely eleven. The following are sexual distinctions. In the male, the tail and legs are longer in proportion to the body; the former is nearly (in some specimens quite) two-thirds of the entire length; the hind leg, applied to the side of the abdomen, reaches to, or passes beyond, the carpus of the fore foot: the ante-anal lamella is shorter and broader, or more transverse: the under side of the base of the tail is flattened, with a slight longitudinal depression in the middle just behind the vent; during the season of sexual excitement the base of the tail is much dilated at the sides, appearing swollen. In the female, the abdomen is longer, and the tail shorter, the latter being often not more than half the entire length: the hind leg barely reaches to the tips of the claws of the fore foot: the ante-anal lamella is longer in proportion to its breadth, and of a more decided hexagonal or pentagonal form: the base of the tail is rounded, and convex underneath, and never dilated at the sides*. (Colours). Extremely variable. Upper parts generally cinereous brown, more or less dark, often tinged with bluish green; a dark list down the middle of the back, with parallel fasciae at the sides; these last broader than the former, commencing behind the eyes, and sometimes extending to near the extremity of the tail; between the mesial list and lateral fasciae, are one or more rows of black spots, and sometimes the same number of yellow ones: under surface of the body and base of the tail, and sides of the abdomen, in the male, bright orange, more or less spotted with black; in the female, generally pale yellowish green without spots. Obs. In some individuals, the whole of the upper parts are plain cinereous brown, without any markings whatever.
* Some of the above distinctions were first pointed out by Mr. Gray in a communication made to the Zoological Society, in May 1832. (See Proceed, of Zool. Soc. 1832. p. 112). I have myself since examined a large number of individuals, and confirmed the accuracy of them.
An extremely abundant species in all parts of the country, frequenting heaths, moors, woods, sand-banks, etc. Is fond of basking in the sunshine, and in warm weather is extremely active. Forms a retreat under ground, in which it resides wholly during .Winter. Is first seen in March, or early in April. Feeds principally on insects. Is ovovivipa-rous; the young broods appearing in June or July. Tail extremely brittle, but, when broken, gradually reproduced. The renewed part, however, according to Duges, never acquires vertebrae.
Trans, vol. vii. p. 50.
This supposed species is principally characterized by the circumstance of the " tail bulging out a little below the base, which gives it the appearance of having been cut off and set on again." I am indebted to Mr. Gray for a suggestion, which he has since published in the Proceedings of the Zoological Society, (1834. p. 101). that it is nothing more than the male of the common species in summer, when under the full influence of sexual excitement. I think this extremely probable.
Trans, vol. vii. p. 51.
"Head very light brown above, with four dark spots; yellowish white beneath: back with a black line along the middle, reaching from the head to about half an inch beyond the hind legs; on each side of this a broader one of dark brown (these beyond the black line unite, and reach to , the end of the tail); next to these succeeds a fine yellow stripe that extends to the end of the tail; then a black one, which reaches no further than the middle line, and afterwards a dark brown stripe mixed with a few yellow spots extending to the end of the tail: a little above the hind legs, in some specimens, is a slight division of the scales, forming a transverse line: belly yellowish white, with a few black spots: tail, under part dirty white, spotted with black as far as within an inch of the end; the remainder marked lengthways with long bars of black: legs dark brown spotted with black. Length seven inches and upwards." Shepp.
Another species instituted by Mr. Sheppard, but too imperfectly characterized to rank as certainly distinct from those already described. Mr. Sheppard states that he once saw a specimen above a foot long, a length to which, I believe, the common L. agilis never attains. Unfortunately, however, this gentleman has in his description almost entirely confined himself to noticing the colours, than which, in these Reptiles, nothing can be more variable*.
Before concluding this account of our British Lacertce, it may be stated that several other allied species, formerly confounded under the general name of L. agilis, are known on the Continent, some of which may possibly occur in this country, although hitherto overlooked by naturalists. Pennant speaks of a Lizard, " which was killed near Wos-cot, in the parish of Swinford, Worcestershire, in 1741, which was two feet six inches long, and four inches in girtht." He adds, that " another was killed at Penbury, in the same county." It is very possible that these may have been the L. ocellata of Daudin, which is found in the South of Europe, and which, according to Duges, sometimes exceeds two f No further light is thrown upon this species, in the Illustrations of the Natural Histori/ of Worcestershire, lately published by Dr. Hastings, who simply alludes to the circumstance, as mentioned by Pennant.
* Mr. Sheppard thinks that this species may be the Lacerta anguiformis of Ray. It is clear, however, that Ray, in his enumeration of the British species of " Eft or Swift, ' as he terms them, has only copied from Merrett, (Pinax, p. 169). who, I suspect, by the Lacertus terrestris anguiformis in Ertcetis, meant nothing more than our Common Lizard, which he calls anijui-formis, in order to distinguish it from the scale-less Efts, belonging to the modern genus Triton, between which and the true Lacertce, the writers of that day did not sufficiently discriminate. Merrett's other species, viz. 1. Terrestris vulg. ventre nigro-maculato, 2. Parvus terrestrix fuscus oppido rarus, 3. Aquat. fuscus, and 4. Aquat. niger, are probably all referable to one or other of our two well-known British species of Triton, being called terrestres or aquadct, according as they may happen to have been found on land or in water.
In the event of their occurring to any future observer, it may be useful to mention that the L. ocellata, independently of its great size, may be easily distinguished by the circumstance of its having the occipital plate very much developed, and at least quite as large as either the frontal or parietal plates *: it also possesses eight or ten longitudinal rows of abdominal lamellae.
Another species, which may be briefly alluded to, is the L. muralis of Latreille, very common on the Continent, and apparently closely resembling our own L. agilis, from which, however, it would seem to differ in having the temples covered with very small granulated scales, resembling those of the back, in the middle of which is one circular plate t: the number of femoral pores is also much greater, varying from eighteen to twenty-five. It may be stated, that Mr. Gray is of opinion that this species is identical with the Common Lizard of this country. Judging, however, from the descriptions of French authors, I cannot but consider this as at present doubtful ‡.