ACTION ON THE FROG'S HEART. 499 



middle loops were both dry, and the mucous membrane was 

 normal in appearance, except slight congestion at the place of 

 ligature between the upper and middle loop. The lower loop 

 contained several c.c. of turbid greyish fluid. 



The intestinal secretion is thus seen not to be increased by 

 the drug. 



Action of Casca on Circulation. 



Experiment XXYII. 



Preliminary Uxperiments on Frog's Heart, 



A watery solution of the alcoholic extract and a standard 

 salt solution were prepared ; the hearts of- two frogs of about 

 the same size were them removed, and placed for a minute or 

 two in -75 per cent, salt solution. When they had recovered 

 from the shock of removal, and were beating regularly, one was 

 placed in the casca solution, the other in the salt one. At the 

 commencement of the experiment the heart. A, placed in salt 

 solution, was beating at the rate of 6 per 10 seconds ; the heart, 

 B, in casca, at the rate of 7*5. Both hearts became weaker and 

 their pulsations slower ; at the end of 50 minutes the heart in 

 casca stopped entirely, that in salt solution pulsated feebly at 

 the rate of 3 per 10 seconds. In 15 seconds more it stopped. 



In Experiment XXVIII we repeated the foregoing experi- 

 ment with a much stronger casca solution. The hearts at the 

 commencement of the experiment were beating at the rate of 

 4 per 10 seconds. At the end of 30 minutes the heart, B, in 

 casca, which had previously got very slow and weak, stopped, 

 while the standard heart. A, was still beating strongly and 

 regularly at the rate of 4 per 10 seconds. 



Experiment XXIX. — March 7. 



The heart of a frog whose cerebrum had been destroyed was 

 exposed. Pulse 72 before injection. 



11 40. Injected 2 c.c. alcoholic solution beneath skin of back. 

 11 50. Pulse 60 ; regular. 



2 K 2 



