146 GUIDE TO THE 
Their skin is frequently prolonged into ridges, crests, 
and frills giving an extraordinary, or grotesque ap¬ 
pearance, while others have their whole bodies covered 
over with . huge spines producing a horrid and formi¬ 
dable aspect. In many, the tail is long, while in others, 
such as the Stump-tails, it is shortened and broadened 
out so as to resemble the head, producing the ap¬ 
pearance, at first sight, as if the animal had a head 
at either end of its body. While some, as above stated, 
are devoid of limbs, or may have them in the most rudi¬ 
mentary condition, the well-limbed lizards have two dis¬ 
tinct kinds of feet, those with ordinary toes and claws, 
like the common Ground and Tree Lizards, and those in 
which the toes are provided with adhesive discs, such 
as the House Lizards or Geckos. There are also the 
so-called Flying Lizards in which the ribs are prolonged 
outwards, forming a framework to which the skin is attach¬ 
ed, and this framework is expanded as the animal leaps 
from branch to branch, or from tree to tree, constituting 
a kind of parachute, generally gaily-coloured, that helps 
to support it in its long leaps. One peculiarity among 
very many lizards is the power they have of changing the 
colour of their skin so as to be in unison with the colour 
of the object on which they may be at the time. This is 
most noticeable in that most extraordinary lizard, the 
Chameleon. The Lizards, with a few exceptions, such 
as the Chameleons and some of the snake-like lizards 
whose internal structure is more nearly allied to that of the 
Chameleon than to any other form, have a hard horny 
covering, generally of overlapping scales, while in the 
chameleons and their allies the skin is soft. In a few 
lizards there is a regular bony armature beneath the 
