RESPIRATION 



97 



the temperature (Rogers and Lewis, 1914) and this is confirmed by 

 Conroy (1960), and can be influenced by injected adrenaline and 



5 minute intervals 



Fig. 30. Effect of drugs on heart beat of Lumbricus. (a) effects of 

 acetyl-choline (ACh) 10~^ and lO"'^ and recovery in saline (Sal.) 

 on one heart in a worm from which the ventral nerve cord was 

 removed from segments 4—18. (b) effect of acetylcholine on dorsal 

 vessel of an earthworm, (c) effect of acetylcholine after atropiniza- 

 tion and after washing out the atropine, (d) and (e) effects of adrena- 

 line (Adr.) on two earthworm hearts. Each point represents the 

 average of several measurements (from Prosser and Zimmerman, 



1943). 



acetylcholine (Prosser and Zimmerman, 1943). The natural 

 occurrence of these substances has recently been conclusively 

 demonstrated in oligochaetes. Muscular movements of the gut and 



