THE LIZARDS 95 



appendage may save its owner's life in time of danger. 

 Suppose a limbless lizard — a Glass "Snake" — is pursued 

 by an active, reptile-eating serpent. The former's stiff, 

 undulatory movements are hopelessly slow in compari- 

 son with the sinuous glide of the pursuer. In a moment 

 the snake has seized its prey. There is a quick twist and 

 instantly the snake is busily engaged in subduing what 

 appears to be its frenzied victim. Actually, this is 

 what has happened: — In that twisting movement the 

 lizard has snapped off its tail. The muscles of the 

 discarded member have been thrown into a state of 

 great excitability — evidentl} 7 a provision of Nature. 

 Meanwhile, an abbreviated lizard has, under cover of 

 the excitement occasioned by the antics of the tail, glided 

 slyly for a safe retreat. 



In catching some of the ground lizards among leaves 

 — by slapping the hand down suddenly over a stalked 

 specimen — the writer has many times been deceived and 

 permitted lizards to escape, owing to a reptile's tail 

 having become detached by the blow when it snapped 

 and twisted among the leaves with such a commotion 

 that the hand involuntarily made a fresh grab for it; 

 then, a second commotion showed the consequent escape 

 of the lizard itself, which had been primarily the 

 prisoner. A number of the geckos run away from dan- 

 ger with the thick tail well elevated and the animal parts 

 with the caudal member at barely a touch, when the tail 

 jumps and wriggles in a manner sure to attract the 

 attention of the enemy. 



In this casting off of the tail the organ is not 

 "disjointed" as is often the popular idea. Owing to 

 a curious structure of the caudal vertebra? the break 

 occurs in the middle of a vertebral joint and the broken 

 end of bone immediately begins a reconstructive proc- 



