3 4 o RESEARCHES ON IRRITABILITY OF PLANTS 



solution is the very reverse, inducing tonic contraction and 

 arrest in systole (fig. 189). 



I find these effects repeated in an astonishing manner in 



Fig. 1* 



g. Arrest of pulsation of Desmodium in diastole, by 



the action of dilute lactic acid. 



Fig. 189.— Arrest of pulsation of heart in systole, by the action 

 of dilute NaHO. (Gaskell.) 



I\ U H !\ l\ l\ 



^Vvvvv 



Fig. 190. — Arrest of pulsation of Desmodium in systole, by the action of 



dilute NaHO. 



the pulsation of Desmodium. The internal application of 

 dilute solution of lactic acid is seen to induce an arrest in a 

 state of diastolic relaxation (fig. 188). The application of 



