1 66 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 J to 4| 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 SCWCID^. 



The preceding family is connected with the one we have now to consider by a 

 small group of five African genera constituting the family Gerrhosauridce, 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 fossre 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 Lacertidce. 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- 



