Hemidactylus, likewise a widely distributed genus, with many species. The digits are dilated, inferiorly with two rows of lamellae; the clawed joints are slender, bent at an angle, and rising from within the extremity of the dilated portion. H. turcicus, between 3 and 4 inches long.–The upper parts of the body are covered with minute granules, mixed with larger tubercles. The abdominal scales are small and slightly imbricating. The male has several pre-anal pores. The tail is covered above with minute scales and tubercles, below with a series of large transversely dilated plates. The general colour is white below, brown above, with darker spots, and with white specks on many of the tubercles. This species extends from Southern Portugal and Spain to Karachi. Like Phyllodactylus and various other kinds of Geckos, the body is semi-transparent; so much so indeed that the white eggs shimmer through the body in certain lights.
Tarentola mauritanica s. Platydactylus facetanus.–The digits are strongly dilated, with undivided lamellae below, and a flat, nail-like scute on their upper surface near the tip. Only the third and fourth digits are clawed. Femoral or pre-anal pores are absent. The upper parts are covered with scales and granules, and bear several longitudinal rows of strongly keeled, large tubercles; the under parts have hexagonal scales. General colour above greyish-brown, with darker or lighter markings; with a dark streak through the eye. Total length of large males about 6 inches. This species is one of the commonest Geckos in the Southern Mediterranean countries. In Portugal it extends northwards to the Douro. It has been introduced by ships into the ports of Cette, Toulon, and Marseilles. It is easily kept in captivity, like most Geckos indeed, provided they are supplied with a variety of insect-food, water in the shape of drops, and suitable places to hide in. A female, which I had received from Algiers in a little tin box, with a lump of meat (presumably its food!), laid two eggs six weeks after its arrival. This was towards the end of April. Towards the end of June in the same year it again laid two eggs, measuring 13 × 10 mm. Another specimen laid in June in two successive years. These and other Geckos live very well in a greenhouse, or in a large glass cage. They change colour most adaptively. They hunt preferably at night for insects, which are stalked and then suddenly rushed at. Drops of water are taken by a lapping motion of the tongue. For sleeping-places they selected bits of hollow bamboo, but these had to be vacated when some tree-frogs crept into them for the daytime, and the Geckos took to some curved pieces of bark, on the under side of which they slept, with their backs downwards. This is, by the way, a favourite position of rest of most Geckos. But Stenodactylus guttatus of Egypt lies flat on its belly, tucks the fore-feet under and inwards like a cat, rests the head upon them, and stretches the hind-limbs out backwards. The little Geckos are rather intelligent. They take no notice of a finger put against the other side of the glass to which they happen to cling; but when the hand is put inside their cage and approaches them too near, they dart off suddenly. When driven into a corner they wriggle and wag their tails, or even raise the latter, perhaps as an invitation to grasp it, in which case it would of course break off. When caught, they emit feeble sounds, and attempt to bite with the mouth widely open. During the moulting, which takes place at least twice a year, in the spring and in the autumn, the skin peels off in flakes; if, as happens sometimes, the skin upon the lamellae is not stripped off neatly, these refuse to act, and the creature cannot climb until all the old skin has been rubbed off.
In their native haunts they are very regular in their habits. Favourite resorts of theirs are old olive trees or oak trees, the rough and cracked bark of which affords excellent places for hiding in. Hollow trees are of course preferred. Not a single specimen is seen during the early hours of the morning or in the forenoon; but when the sun has become broiling hot, and our own shadow passes over the stem of a tree, we become aware of flitting little shadows which jerk over its surface. These are Geckos which had been basking, motionless; very dark grey, almost blackish, just like the colour of the grey bark upon which the last wet season's moss has been scorched to a black cinder. It is difficult to espy a Gecko whilst it is glued on to such a tree. Only the little beady eyes betray it, watching you carefully. Nothing appears more easy than to catch that motionless thing. You put out your hand and it is gone; like a flash it has moved a foot higher up, or down, to the right or to the left, just where you least expected it to go, and there it clings on motionless as before. It does not seem to run; it glides along, dodging over to the other side of the stem and back again. There is system in its motions, since, taking a last leisurely look around, it gently disappears in a rent or hole. Towards the evening, or when the shadows become longer, the Geckos become lively. One after another appears on the surface, upon the tree, or at the entrance of the cave, and they all move about in their peculiar rushing jerks. Spiders, flies, mosquitoes, moths, form the principal diet, and the hunting goes on well into the night. Where a gecko has been seen once it is sure to reappear the next day at the same hour. Those which take up their abode inside a house become almost domesticated. They are strange sights when hunting for flies, running up and down the papered walls; but we fairly gasp when they come to the upper corner, calmly bend over, and with the next jerk slide along the white-washed ceiling. We are accustomed to flies performing such feats, but at animals five inches long, supple and fat, we are inclined to draw the line. However, that is the way of Geckos, and–be it confessed–the more we ponder over the mechanism of their fingers and toes, the less we comprehend how such little vacua can support or suspend such heavy creatures from a dry and often porous surface.
Gecko.–The digits are strongly dilated with undivided lamellae. All, except the pollex and hallux, have a very short compressed terminal phalanx with a retractile claw. Males with femoral or pre-anal pores. This Eastern genus includes some of the largest of all Geckos.
G. stentor of the Malay countries reaches a length of 15 inches. G. verticillatus s. verus s. guttatus ranges from Eastern Bengal to China and through the Indian archipelago. It grows to about one foot in length. The head is large; the back is covered with small granules and about a dozen rows of large tubercles. The tail, when intact, and the belly are covered with scales, those of the tail being arranged in transverse rows, several of which make up distinct rings. The upper parts of the body are grey or yellowish with red spots and vermiculations. According to Theobald[[151]] it lays about eight hard-shelled white eggs as big as a musket-ball, cementing them to trees, rocks, or secluded buildings. The cry is "touk-tay," several times repeated, and ending in a long-drawn out, diminuendo, guttural rumble. This animal does not confine itself to insects, but eats young rats also. Dr. Mason has seen it devour smaller species of house-lizards, and Theobald has seen it seize a bat flying round the room, and devour it.
Tennent[[152]] tells the following story about one of these creatures: "In an officer's quarter in the fort of Colombo, a Gecko had been taught to come daily to the dinner-table, and always made its appearance along with the dessert. The family were absent for some months, during which the house underwent extensive repairs, the roof having been raised, the walls stuccoed, and the ceilings whitened. It was naturally surmised that so long a suspension of its accustomed habits would have led to the disappearance of the little lizard; but on the return of its old friends, it made its entrance as usual at their first dinner the instant the cloth was removed."
Ptychozoon.–The digits have the same structure as described in the genus Gecko, but they are entirely webbed. The extraordinary feature of Ptychozoon is the membranous expansions on the sides of the head, body, limbs, and tail, which are said to act as parachutes. P. homalocephalum, the only species, inhabits the Malay Islands and the Malay Peninsula. It reaches a length of 8 inches. A specimen obtained by F. H. Bauer in Java, in the month of November, laid two eggs a few days after its capture. One young was hatched in the middle of the following May, and two days later another came out of the second egg. The characteristic folds of the skin were already clearly discernible.
Sub-Fam. 2. Eublepharinae.–Differing from the true Geckos by their procoelous vertebrae and the fusion of the two parietal bones into one. The eyelids are not reduced, but remain functional. This sub-family is undoubtedly a heterogeneous assembly, as indicated by the very scattered distribution of its few species (about seven), in India, West Africa, and Central America.
Fig. 121.–Ptychozoon homalocephalum. × ⅔.