1 
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had distended testes and six females were pregnant. On Hull, none of 
the specimens collected were in reproductive condition. 
Territorial behavior was exhibited by R. exulans on several occasions 
on Hull. In the coconut forest, individual rats maintained a certain 
territorial space; intruders were either Chased away by loud squeaks or by 
charges on the part of the defender. Territorial space was evidently 
not maintained in areas where food was present. Six rats fed together on 
A 
a melon that had been cut open and left on a trail. 
Most of the specimens were collected by hand or with a .22 pistol. 
Museum Special snap traps were usually ineffective because they were 
sprung by hermit crabs. 
House Mouse 
( Mus t musculus ) 
Mus musculus were observed on only one island on SIC 15 * Four nouse 
mice were sighted but not collected on Baker Island. According to past 
* 
records, the population of Mus musculus has been substantially, perhaps 
by cats, reduced in the last three to four months. At least three cats 
were seen on the island. 
All four M. musculus were observed in a Tribulus - Boerhavia association. 
Fifteen Museum Special snap traps were set out at night on piles of 
lumber and on barrels out of the reach of hermit crabs but no mice 
were caught. 
