JOURNAL OF ANIMAL BEHAVIOR 



Vol. 3 NOVEMBER-DECEMBER, 1913 No. 6 



LITERATURE FOR 1912 ON THE BEHAVIOR OF 

 LOWER INVERTEBRATES 



S. J. HOLMES 



The University of California 



The experiments of Allee (i) were performed mainly upon 

 Asellus communis, Specimens from streams gave a high per- 

 centage of positive rheotactic responses. Pond isopods, on the 

 other hand, showed a weak positive rheotaxis, and were fre- 

 quently indifferent. In general the oxygen content of streams 

 was found to be higher than in ponds. That this fact may 

 afford at least a partial explanation of the different responses 

 of pond isopods and stieam isopods is indicated by results of 

 experiments which showed that the positiveness of the rheotaxis 

 is decreased by lack of oxygen. In general agents that act as 

 depressants (chloretone, potassium cyanide, carbon dioxide, low 

 temperature, etc.) reduce the rheotactic response, while agencies 

 that stimulate metabolism, such as oxygen, caffein and increase 

 of temperature within certain limits, increase this response. 



Bauer (2) has shown that the behavior of Pecten lacobaeus 

 L. is unusually complex and shows many interesting adaptations 

 to its habitual environment. This species feeds mainly on 

 microscopic algae, and seeks well lighted situations which nat- 

 urally afford more of its accustomed food. During the process 

 of swimming, which is accomplished by opening and closing the 

 valves of the shell, the animal is unable to orient itself to the 

 rays of light. Orientation is effected when the Pecten comes to 

 rest on the bottom, by forcibly expelling the water on the side 

 that is turned away from the light. After being turned so as 



