The Behavior of Loxophvlliini 409 



rhe rare of the back and forth movements between a piece contain- 

 ing the sensitive anterior end of the body and a piece from any 

 other region. E\en very small pieces show the same rhythm. 

 On account of its rhythmical activity Loxophyllum does not 

 have to wait for something to turn up in order to acquire new 

 experiences. Its life is one of continual trial. Only to a compar- 

 atively slight extent is its activity, under usual circumstances, 

 directed by external conditions at all. It goes forward, back, 

 turns orally, goes forward and back agam, and so on, repeatedly, 

 through its own inherent activity. In many of the lower organ- 

 isms behavior mainly consists in more or less direct responses to 

 external stimuli with little spontaneous movement, but unless 

 something unusual affects it Loxophyllum keeps circling about 

 near the same place for a long time. When it meets with a strong 

 or injurious stiniulus it has its own methods of getting out of the 

 way, but its ordinary behavior is mainly guided by internally 

 initiated impulses. 



COMPLEXITY OF BEHAVIOR 



From the preceding account it is evident that the behavior of 

 Loxophyllum is considerably more varied than that of Para- 

 mecium and many other infusoria. Paramecium, for instance, 

 has a very few stereotyped modes of behavior, such as spiral swim- 

 ming, the motor reflex, acceleration of forward motion when 

 lightly stimulated at the posterior end, the thigmotactic response, 

 and bending the body when crowded among obstacles. Loxo- 

 phyllum has not only all these responses, but several others in 

 addition, /. e., gliding movements, regular changes in the form 

 of the body accompanying forward and backward movements, 

 small feeling movements of the tip of the body, undulations of 

 the oral margin, twistings, turnings, and contortions of the body 

 under various conditions, special movements involved in swallow- 

 ing large objects, and several kinds of righting movements. This 

 greater complexity of behavior is probably a consequence of the 

 fact that most of the creature's life is spent in contact with solid 

 objects. It appears to be a general rule that the behavior of the 



