62 ON THE "GILA MONSTER." 



a clog. For a while the sand was dug out directly, until 

 it began to pour back ; then a position was taken up on 

 the top of the heap that had been made, and it was thrown 

 still farther back; gradually working forward, conditions 

 were soon made favorable for continuance of excavation 

 at the bottom of the burrow. At the depth of about a 

 foot the body was hidden and only the tail exposed. This 

 depth appeared to be satisfactory for a time, and the dwell- 

 ing was occupied as if complete. 



The tail is club-shaped, near six inches in length by one 

 and a half in diameter, and retains its thickness back tow- 

 ard the end where it rather abruptly tapers to become more 

 slender and pointed. When the tail was sticking out of the 

 excavation, as in digging, the slender extremity moved 

 from side to side, back and forth and around, with more 

 flexibility than was to be expected from its size, as if con- 

 stantly on the alert for unseen danger. The organ is very 

 sensitive. While asleep the tail was stowed as if to in- 

 sure its safety ; it was either extended directly back into 

 the burrow, half of the body remaining outside, or, when 

 the animal was wholly under cover, it was bent forward 

 along the side. In sleep, the body lies flat on the sand 

 and the arms were usually stretched back, palms upward. 

 After a few weeks, less care was taken in regard to enter- 

 ing the burrow during the day, and the naps were taken 

 anywhere in the box. 



The box was not well placed for the sunshine ; it was 

 covered with a strong netting. Some attempts to get 

 through the net one morning caused the occupant to be 

 taken by the shoulders and lifted over into another cage 

 where he might get the full benefit of the sun. This was 

 quietly enjoyed until the sun had passed, then there 

 was another attempt on the cover, followed by return to 

 the first box and retreat into the hole. This came to be the 



