774 Proceedings of the Royal Society 
The sciatic nerves apparently retained their normal excitability 
or nearly so. 
With very large doses, such as 2 to 3 grains, the injection had to 
be made at several points, owing to the amount of fluid. The poison 
takes effect in a few minutes, the frog gradually becoming more and 
more paralysed. Respiration ceases, and it lies in whatever position 
it may be placed. The heart is also arrested, and death occurs gene- 
rally without any symptom of increased reflex excitability. 
When benzoylecgonin is given by the mouth, both species of 
frog recover after one grain. It is more slowly absorbed, and the 
effects last longer than when given hypodermically. When it is 
injected into the anterior abdominal vein, the symptoms are also 
similar. 
Division of the spinal cord at the medulla has no effect on the 
convulsions. 
Ligature of one iliac artery before administration does not exclude 
the corresponding leg from the tetanus, while division of one sciatic 
nerve causes a cessation of the spasms in the same limb. 
If the brain be destroyed, the tetanic stage comes on earlier and 
with smaller doses than in the uninjured animal. 
The administration of curara prevents or stops the convulsions. 
Chloroform abolishes them also, but they gradually return as the 
effects of the anaesthetic wear off. 
From the foregoing general description it is evident that the 
action of benzoylecgonin is very similar to that of caffein on frogs. 
The muscular and central nervous systems are primarily affected, 
the heart suffering less markedly while the peripheral nerves remain 
apparently untouched. 
Action on the Individual Systems. 
Heart and Circulation . — If the excised heart be placed in a 1 
per cent, solution made with f per cent, salt solution, there occurs 
at once an increase in the number of beats and a more marked 
systole. The increased rate is maintained for 10 to 15 minutes, after 
which it slowly falls ; the heart finally stopping in diastole. Satu- 
rated solutions rapidly killed the heart. 
To observe the action on the heart in situ , the frog was fastened 
on its back in the ordinary way, the rate determined, and the 
