80 STORY OF THE JIEPTILES 



means of expressing the emotions, and, since we find 

 it (alone) liighly colored occasionally, it is probably 

 an ornament also. Some run witli it curled over the 

 back like a scorpion's, and sucli lizards have been 

 wrongly called " scorpions " because of this habit. In 

 this connection, some lizards have a peculiar use of 

 the tail which is found in other creatures as well, but 

 not frequently. It is that of making with it a sort of 

 unconscious prayer and sacrifice for the safety of the 

 body. In the European lizards, in our glass- or 

 jointed-snakes (see Fig. 39), and others, not only are 

 the bones of the tail loosely attached to each other, but 

 they have a sort of membrane, which runs between the 

 joints and extends outward through the muscles and 

 skin even. By this means the whole tail is "jointed " 

 and the parts may be separated, without loss of much 

 blood, as the parts of an orange come aj^art, without 

 any loss of the juice. 



If a pursuing enemy grasp this tail, it breaks off 

 readily and may allow the body to escape, as if the 

 creature thought it better to go maimed into salvation 

 than to go whole into destruction — especially since the 

 part lost, in such' cases, is soon regrown. 



Seriously there is no thinking about it, by the 

 creature. In some instances the exertion even of 

 trying to escape may break off the tail of our glass- 

 snake, and leave it wriggling for a while to attract 

 the enemy's attention ; and so purely mechanical is 

 this action that sometimes the body itself has been 

 known to turn and swallow the squirming thing. 

 All stories about these parts reassembling are myths. 



