120 . PEARSE. 



most crabs manifested a choice for a particular locality. On 

 one occasion the writer was sitting motionless at the edge of 

 the estero when a female fiddler came out of a burrow beside 

 him. He quickly clapped a foot over the hole so that the owner 

 could riot enter. She sat perfectly motionless for fifteen 

 minutes. Then, as the writer slowly moved away his foot, she 

 made a dash to the spot where the burrow had been and tried 

 persistantly to enter, but was not able to do so on account of 

 the mud that had been pressed down in such a way as to close 

 the hole. She remained thus until the writer frightened her 

 away by bringing his hand near her. 



A number of peculiarly marked fiddlers were snared with a 

 noose of thread as they emerged from their bui-rows and then 

 carried various distances to see if they would return. Although 

 the results of these tests, as shown in Table II, were quite 

 variable, they indicate that fiddlers have some power of associa- 

 tion in connection with the situation they may have chosen for 

 a burrow. Although only 3 out of 11 crabs returned to the 

 same spot, the writer was convinced that the behavior of these 

 3 showed an association for a particular place. 



Table II. — Showing results of moving fiddler-crabs various distances from 

 their holes. 



Number of individual. 



Distance 

 moved in 

 meters. 



Returned — 



To same 

 hole. 



To same 

 locality. 



1___ ._. 



9.0 

 6.0 

 4.5 

 1.8 

 6.0 

 6.0 

 5.4 

 2.4 

 6.0 

 4.6 

 2.4 



No 



No _ 



No 



Yes 



Killed ._- 



No 



No 



Yes 



No_ 



No 



No 



No. 



No 



No. 



Yes. 



Killed. 



Yes. 



No. 



Yes. 



No. 



No. 



No. 



2 



3 



4 -. _ 



B 





7 





9 - - 



10 







Numbers 1, 2, 3, 7, 10, and 11 were moved to new situations 

 where high ground prevented them from seeing their burrows; 

 1, 2, 8, 5, and 11 were never seen after the day they were moved ; 

 3, 6, 7, 9, and 10 at once occupied burrows in the new location, 

 some of these dug new burrows and some may have occupied 

 those already dug. Although number 1 was in plain view of 

 the burrow where he had been captured, the writer could not 



