THE LIZARDS 125 



tion. It seems probable, too, that the bristhng tail of 

 the Mastigure serves as an effective means of closing 

 the animal's burrow to intruders ; for rash indeed would 

 be the antagonist trying to force its way past that spike- 

 studded weapon. 



By some writers who have observed the Mastigure in 

 a captive state the lizard has been described as being 

 "stupid" in a refusal to feed and become accustomed to 

 its quarters. Such declarations are altogether unjust. 

 Nature permits no stupicl creature to live. What ap- 

 pears to be stupidity on the part of a wild animal is 

 bewilderment among conditions wholly unsuited to it, 

 mingled with a vague longing for liberty. If a human 

 were to be suddenly transferred from the comfortable 

 center of his dwelling and diversions, to the desert 

 wastes of animals he has characterized as stupid, what 

 frenzied wanderings and flight from wild beasts would 

 be his lot! Consider a lizard created for the dunes and 

 sun-baked rocks of the desert transported thousands of 

 miles to the low temperature and humidity of a tem- 

 perate climate, then placed in a small, glass-fronted 

 cage. The prevailing temperature is lower than that 

 the reptile has sought to avoid each night in its desert 

 home by retreating into a burrow in the heated sand. 

 Can the captive be blamed if it mopes, or dashes against 

 such queer substance as glass, or steadily refuses food? 

 One fault of many observers has been the neglect of 

 furnishing enough heat for captive reptiles. Such ob- 

 servers have described all tortoises as slow ; yet the writer 

 has seen species, kept in a temperature almost unendur- 

 able to a man, get over the sand at almost a run. To 

 make a INIastigure display its normal Advacity it should 

 be kept in a temperature of from 85 to 95 degrees 

 Fahrenheit. 



