APPENDIX I 



LIST OF THE FAUNA 



MAMMALIA. 



(1) The Pulu Tikus Race of Mios dccumanus. 



During Darwin's visit the only rat in the islands was the 

 Pulu Tikus race, and of it he says : " These rats are con- 

 sidered by Mr. Waterhouse as identical with the English kind, 

 but they are smaller and more brightly coloured " (" Naturalist's 

 Voyage," p. 461); and Wallace ("Island Life," p. 275) adds : 

 " We have here an illustration of how soon a difference of 

 race is established under a constant and uniform difference 

 of conditions." 



In the seventy years that have passed since Mr. Water- 

 house described the rat, the difference appears to have become 

 more marked, and a description of the race is justified for the 

 reason that the modern introduction of rat virus into the atoll 

 may possibly exterminate it. 



External Appearance. — The rat is a slenderly built and sleek- 

 looking animal ; its general colour is a warm russet-brown. 

 The fur of the back is coarser, and some hairs stand out which 

 are almost black, and are 30 mm. in length; these long dark 

 hairs are more numerous over the hind end of the body than 

 over the shoulders. The general colour of the body is a rather 

 rich brown, the belly being but little lighter than the back in 

 most specimens. The shorter hairs are grey at the base and 

 bright red-brown at the tips ; the longer hairs are dark brown 



to black. The fore limbs are somewhat lighter than the rest 



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