14 



A T otes on the Hawaiian Rat. 



Summarizing the results concerning native species from all 

 the localities visited and mentioned in this and Dr. Stone's article 

 preceding, we get, if the writer's identification of the material be 

 correct, on the islands of — 



Kauai : 



Sand-dunes, Weliweli. No traces of rats. 

 Sand-dunes, Mahaulepu. Skeletal material. 



Oahu: 



Reef islet of Popoia. Living rats. 



Reef islet of Kekepa. Natural conditions for rats similar to Popoia. 



Volcanic coastal islets 



of Mokulua. No traces of rats. 



Sand-dunes, Heleloa. Skeletal material and possibly living rats. 



Maui : 



Sand-dunes, Wailuku. Skeletal and fresh material. 



Kahoolawe : 



On barren coast. Skeletal material, with introduced species. 



Except for Kahoolawe, these observations cover a period 

 of less than two years. Only at Popoia and Kahoolawe was there 

 any amount of time spent. When we consider that the results 

 obtained were mostly due to accidental discoveries through brief 

 visits made only as time permitted, the conclusion seems obvious 

 that the Hawaiian rat may yet be found alive in many other 

 localities which it may have reached, where conditions are favor- 

 able for its preservation. 



In seeking for these favorable conditions, we would ordinarily 

 select localities from which the native rodent's introduced com- 

 petitors or natural enemies (large rats and mongoose) are debarred 

 by natural conditions; which do not furnish sufficient food or 

 cover to attract them ; or to which they have not so far extended. 

 This much has apparently been found in the shore-lying islets and 

 coastal sand-dunes, which are common in this group. Among the 

 former, for instance, on Oahu (see map) may be Kekepa (raised 

 reef) and Mokolii (volcanic). Other islands, Kapapa (raised reef) 

 and Mokumanu, Mokulua, and Manana (all volcanic) may be too 

 distant. Moku o L,oe (volcanic), in Kaneohe Bay, should be a good 

 locality, and it is reported as being overrun with rats of a species 

 not known at present. This island was recently inhabited, and is 

 so frequently and easily visited that the rat may well prove to be 

 of an introduced species. 



The sand-dunes, used for cattle grazing, are generally covered 



with a sparse herbal growth, sufficient perhaps to support the 



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