AUTHORS ABSTRACT OF THIS PAPER ISSUED 

 BY THE BIBLIOGRAPHIC SERVICE MARCH 2 



REACTIONS OF THE PROBOSCIS OF PLAN ARIA 

 ALBISSIMA VEJDOVSKY 



WILLIAM A. KEPNER AND ARNOLD RICH 



From the University of Virginia 



TEN FIGURES 



CONTENTS 



Material and methods ...» 83 



Nervous system 602 



Anatomy of the proboscis 602 



Normal functioning of the proboscis 603 



Reactions of freed proboscis 604 



Factors determining inhibition of the proboscis 607 



(a) thigmotactic conditions 609 



(b) neural inhibition 617 



Reaction to food of freed proboscis 610 



Conclusions 617 



Literature cited 618 



MATERIAL AND METHODS 



The planaria upon which we worked is found in the brooks 

 and spring runs of the mountains about the University of Vir- 

 ginia. Collections were made most conveniently by gathering 

 Vaucheria masses, leaves and stones from the bed of these 

 mountain streams. When such material has been kept in an 

 aquarium jar of tap-water, the worms rise to the surface. We 

 have had no difficulty in keeping these animals for a week or 

 more in tap-water that is free from infusion masses. 



The animals so collected were fixed in chrom-aceto-formalin 

 and aceto-sublimate solutions. Golgi preparations werealso 

 made, but these yielded us no information concerning the nerv- 

 ous system. Iron haematoxylin and Mallory's connective-tissue 

 stain gave us our best results in studying the nervous system 

 of the flat worm. 



83 



