FLATWORMS 



Pharynx 



- Gut 



Excretory 

 canals 



Fig. 11.10. Order Rhabdocoela. .4, a typical rhabdocoel, Mesostoma ehrenberon, showing the 

 simple, rod-like s^ut and the general features of the protonephridial system. B, asexual repro- 

 duction in Stenostomum grande: each of the daughter individuals produced by the first division has 

 undergone further division, and various stages in the formation of new heads are evident along the 

 chain. {A, redrawn, after Steinmann and Bresslau, from E. Bresslau in W. Kukenthal and 

 T. Krumbach, 1933, Handbuch der ^oolosyie; B, redrawn from E. Marcus, 1945, ^oologie, no. 10, 

 University of Sao Paulo, Brazil.) 



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