AUTHOR'S ABSTRACT OF THIS PAPER ISSUED 

 BY THE BIBLIOGRAPHIC SERVICE, MAY 1 



THE ROLE OF THE NERVOUS SYSTEM IN THE 

 RlcENiRATION OF POLYCLAD TURBELLARIA 



J. M. D. OLMSTED 



HopUns Marine Station 0/ Stanfori Uni^nUu ani Depa.«»< 0/ Physiology, 



^ University of Toronto 



NINE FIGURES 



The triclad turbellaria have been supposed to differ tunda- 

 mentally from the polyclads in their powers of regeneration, the 

 To ner being able to regenerate complete individuals from pieces 

 taken from any portion of the body, the latter bemg unable t^ 

 restore anterior parts when the cephalic ganglia are absent. 

 Cne-tiln in t'he polyclads is therefore cont.oiled t^.;-- 

 siderable extent by the central nervous /y«t«"! , J^^^J^^^ 

 strong contrast to the regenerative powers of the triclad, Planana 

 rnacuLta which, according to Morgan ('04), may regenerate an 

 Tt retdividua from a piece entirely devoid of nervous system. 

 M s Uoyd (14), however, found that such a distinction between 

 th se two classi of turbellaria did not hold, for she discovered 

 a marine triclad, Gunda ulvae, which was incapable of regenerat- 

 rnHn anterior end unless the cephalic ganglia were present. 

 This triclad therefore possesses the limited regenerative powers 



°'op;ortui:S' was afforded at the Hopkins Marine Station of 

 Stanford University on Monterey Bay ^^^^^^^^ 

 regeneration of three species of polyclads in orfei to dlSco^el 

 wheth r anv one of them might possess exceptional powers of 

 Regeneration, or whether all would show the same mfluence of the 

 neCus sys em on the regeneration of anterior par s as other 

 Tolyclads'lready reported upon (e.g., ^eptoplana t,e eU^^^^^ 

 Child '04). The three species were found m sufficient numbers 

 under stones in the water of tide pools or imbedded m sand 

 ^Lr the low-water level at low tide, to carry out a series of expen- 



