PLATE 1 



EXPLANATION OF FIGURES 



1 A normal frontonia approaching the end of an oscillatoria fiber prior to 

 ingestion. 



2 Oscillatoria fiber entering the body of the frontonia. Characteristic shape 

 of the organism during the early stage of ingestion of linear objects. 



3 and 4 Turning of the body of the frontonia in order to relieve the stimula- 

 tion at the first tension point (fig. 3, a). 



4 to 6 The body cilia is pushing the frontonia in the direction of the food and 

 thus forcing the end of the object posteriorly along the aboral wall. 



7 and 8 The fiber reaches the posterior end of the organism and causes an 

 elongation of the body of the frontonia. 



9 The fiber breaks and ingestion continues by the oral cilia pulling the mouth 

 along the object. 



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