46 



KANSAS UNIVERSITY SCIENCE BULLETIN. 



Table IV. Mean results in cardiac and respiratory activity and blood pres- 

 sure following injection of different concentrations of MgS04. 



Curve 21. Effect of MgS04 m/64. 



Jiiryo 2' 



"lormal 



f-\ArvrvYM\r\r\- 



Upper curves, cardiac and pressure with Hurthle. Lower, respiratory 

 gill-arch lever. Time, five seconds. At x, injection. Cardiac rate less, 

 force and blood pressure slightly greater; respiratory rate less, force 

 unchanged. 



Curve 22. Effect of MgS04 m/8. 



Curve 22. 



Upper curve, cardiac and blood pressure shows decrease in cardiac 

 rate, slight increase in force and blood pressure, for two minutes. Lower, 

 respiratory gill-arch lever curve; decrease in force, not in rate. 



Curve 23. Effect of MgS04 m%. 



Ourre 23. 



Upper curves, cardiac and blood pressure; rate unchanged, force and 

 blood pressure slightly increase for two minutes, then decrease. Lower, 

 respiratory curve, decrease in rate and force. 



