170 Studies in Animal Behavior 



abundant and of large size. In going forward the 

 body bends orally and frequently undulates about 

 in a very variable manner. The backward and for- 

 ward movements of Loxophyllum may be performed 

 in much the same way for a long period apparently 

 without any external stimulation. The organism is 

 capable of many kinds of behavior under different 

 conditions, but its usual activities are all that con- 

 cern us in the present connection. 



As has been found in other infusorians, the be- 

 havior of pieces into which the organism is cut is 

 closely similar to that of the entire individual. The 

 pieces of this species regenerate so rapidly as a rule 

 that one can actually watch the process going on. 

 An excellent opportunity is thus afforded for study- 

 ing whatever connection there may be between the 

 activities of the piece and the changes of form that 

 occur in it. 



In the regenerative changes of the posterior half 

 of the body, for instance, we find that apparently as 

 a consequence of the elongations and contractions 

 that accompany the forward and backward move- 

 ments, the general form elongates and becomes more 

 narrow. The cut end is partially closed in by the 

 drawing together of the two margins, the oral side 

 extending over rather more than the aboral (Fig. 

 i). In the movements of the animal it may read- 

 ily be seen that the oral side is pushed ahead as the 

 animal swims forward as if it were making active 

 efforts to stretch itself out. Both margins, how- 



