i66 
LIZARDS. 
warm districts, and thriving well in captivity, it presents nothing specially note¬ 
worthy as regards its habits. 
Fringe-Toed The fringe-toed lizards ( Acanthodactylus ), of which there are 
Lizards. ten species ranging from Southern Spain and Portugal, and Northern 
Africa through South-Western Asia to the Punjab, differ from the preceding group 
by the toes being both fringed on the sides and keeled below; a more or less 
distinct collar occurring on the throat. On the head, the occipital shield is 
wanting, and the nostrils are pierced between two nasal and one labial shields. 
Pores are present on the thigh, and the tail is nearly cylindrical. The common 
fringe-toed lizard {A. vulgaris) is a species of from 4^ to 4f inches in length, 
agreeing with most of its kindred in having the hinder scales of the back but little 
enlarged, and specially characterised by the strong keeling of the scales on the 
upper surface of the tail, and the slight pectination of the toes. It is represented 
by two varieties, one occurring in Spain and Portugal, and rarely in the south of 
France, characterised by the smooth or slightly keeled scales of the back, and an 
African form in which these scales are very strongly keeled, and the coloration is 
brighter. The colour of the adult is greyish or brownish, with faint longitudinal 
series of light and dark spots and lines, and sometimes eye-like blue spots on the 
flanks; the young being longitudinally streaked with black and white, and having 
white spots on the limbs. All these lizards inhabit dry sandy districts, and are 
remarkably shy in their habits, seldom venturing forth from their retreats except 
when the sun is shining brightly. 
The Skink Tribe. 
Family SciNCID u®. 
The preceding family is connected with the one we have now to consider by a 
small group of five African genera constituting the family Gerrhosauridoe, which, 
while resembling the true lizards in having but a single premaxillary bone and 
the presence of pores on the thigh, agree with the skinks in possessing bony plates 
of peculiar structure beneath the scales. The skink tribe, taking their title from 
the lizard commonly known by that name, are a very numerous family, comprising 
upwards of twenty-five genera and nearly four hundred species, and presenting 
great variety of bodily form, some kinds being four-limbed, while others are more 
or less completely snake-like. Agreeing with the true lizards in the characters of 
the tongue and teeth, as well as in the roofing-over of the temporal fossae by bone, 
the skinks differ in having two distinct premaxillary bones in the skull, in the 
presence of bony plates traversed by symmetrical tubules beneath the scales, and 
in the invariable absence of the pores which are generally present in the thighs of 
the Lacertidoe. The limbs, when present, are relatively short, and in some cases 
are reduced to two, and in others absent; the number of toes is very variable, 
even among the members of a single genus; the short and scaly tongue is free, 
and but slightly notched in front; and the drum of the ear is generally covered 
with scales. The eyes have round pupils, and well-developed and generally mobile 
lids, the lower one of which has a large transparent window. The teeth, which 
