1 6 Notes on the Hatvaiian Rat. 



mals could be watched from the room through the uncovered wire 

 at the top. Their reaction to sound and scent was so sharp that 

 they could detect the quiet approach of an observer before they 

 could see him and would then remain motionless, except for their 

 twitching snouts and ears, as long as a person cared to watch from 

 a little distance. A nearer approach to the window would cause 

 a scurry for the sleeping box. Subsequent observations would 

 then be limited to the pair of twitching noses poking out of the 

 box opening. 



The appearance of a person above the cage always terrified 

 them. Later, the cage was changed to a window where the rats were 

 just above the level of one's head when standing on the ground. 

 In this situation, one of the rats became tame enough to eat from 

 (and of) the fingers. However, movement above the cage continued 

 to frighten them as much as ever, and the upper part of the cage 

 was subsequently covered over. 



Noise of any kind disturbed them, particularly the sharp snap- 

 ping of the cage wire when opening the little door, when they 

 would freeze as though expecting to meet their doom. It is evi- 

 dent that any future observations should be conducted in a cage 

 which can be handled noiselessly. 



They are on the move during the whole day, and feed freely 

 at this time. Judging from the noise, however, their greatest 

 activity is in the early part of the night. Their long sleep must 

 take place between 9 p.m and 8 a.m. 



Their food has been bread, cooked meat, bones, fresh, salt and 

 smoked fish, lettuce, sow-thistle, cabbage, wheat, oats, walnuts, 

 apples or anything else in the house. The bones are not closely 

 gnawed. Papaya {Carica papaia) , a fruit of which the imported 

 rats are very fond, destroying man)' on the trees, was refused 

 by those under observation.' A leg of the common rock crab 

 (Grafisus sp.) was also refused, though probably on account of the 

 difficulty of breaking through the shell. They have been observed 

 chasing the common wood-roach, which occasionally crawls into 

 the cage, but the chase stopped as soon as the observer approached 

 the cage from above and the roach escaped. Living sow-bugs and 



"In January, 1917, papaya was fed to and eaten by the male which had 

 been in captivity for twenty months. At this time also the milo seeds were 

 first fed, to the same rat; they were not eaten very readily. 



[266J 



