EXPLANATION OF PLATES. 



PLATE I. 



Experiment 17. — Stromuhr. 



Fig. 1. The norm, after the leech extract, lower line representing seconds, upper line the time required for the filling 



of the stromuhr. 



Fig. 2. Record two minutes after the injection of 2 c. c. of alcohol. 



Fig. 3. One minute after the injection of a second 2 c. c. of alcohol, 4 in all. 



Fig. 4. One and one-half minutes after fourth injection of alcohol, 9 c. c. in all. 



Fig. 5. One and one-half minutes after the sixth injection of alcohol, 13 c. c. in all. 



Fig. 6. After the injection of 28 c. c. of alcohol. 



Fig. 7. After the injection of 48 c. c. of alcohol. 



Fig. 8. After the injection of 60 c. c. of alcohol. 



PLATE II. 



Experiment 18. 



Fig. 1. The norm, after the leech extract, showing pressure in the carotid artery and time required for the filling of 



the stromuhr. 

 Fig. 2. After 3 c. c. of alcohol. 

 Fig. 3. After 7 c. c. of alcohol. 



PLATE III. 



Experiment 21. — Williams' s apparatus. Frogs heart. 

 Fig. 1. The norm. 



Fig. 2. With the use of one-half per cent of alcohol. 

 Fig. 3. With the use of 1 per cent of alcohol. 



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