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THE AMERICAN NATURALIST 



[Vol. LIII 



sur des pentes creusees artificiellement et diversement inelinees, que ces 

 animaiix peuvent tout aussi bien descendre que monter les pentes dans 



Apres avoir elimine sueeessivement divers faeteurs, je me suis arretee 

 a cette hypothese: les Crabes se dirigent du cote de la mer attires par 

 rhumidite dogagee par celle-ci; il y aurait hydrotropisme. 



Drzewina noticed the character of the behavior of the 

 crabs after a heavy rain. The peculiarity of this behavior 

 seemed to present additional evidence that the movements 

 of the crustaceans, previously mentioned were responses 

 to the moisture from the sea. At such a time the ground 

 was very moist. Therefore there was no longer a sharp 

 contrast between the land and the sea, with respect to the 

 amount of water vapor given off by each. The crabs did 

 not go directly toward the sea; but some of them moved 

 obliquely to the right and to the left; others followed a 

 zigzag course, parallel to the sea ; while still others climbed 

 a slope and proceeded in a direction opposite from the 

 sea. I will record these very interesting observations in 

 her own words (1908, p. 1010) : 



Plusieurs faits que j'ai o1)sorves viennent a I'appui de eette hypothese. 

 Apres uno pliiic .•ibon.lant.". h' >nl ,'tnnl Iniiuido. quand on depose les 

 Crabes sur yvnw >al)I.M,<,'. il> w se .lii-iuvni ].a> diroftemont vers la 



This observer found that, when a crab was placed in 

 front of a kind of dyke, which at low tide separated two 

 bodies of water, tlie animal did not respond by moving 

 Inward either body of water, but, instead, it took an inter- 

 in. 'diate dirwtion, and walked toward the dyke. She 

 iv,M,id(Ml t]ie>(> UwU as follows (1908, p]). 1010* 1011): 



