1874.] Poison of Indian Venomous Snakes. 99 



10.57. Ligature applied. A considerable quantity of blood was lost. 



10.58. A considerable quantity of dried cobra-poison dissolved in water 

 was injected into the dorsal lymph-sac. Immediately after being released 

 the frog jumped about, but became quiet in a minute or so. 



11.28. Made some voluntary movements. 



11.45. Acetic acid to fore feet causes weak reflex movements in both 

 fore feet ; stronger in hind feet, especially in right. 



11.55. Acetic acid to right forearm caused vigorous kicks of right 

 hind leg. Acetic acid affected right leg in 10 seconds. No motion in 

 any other part of body. Acetic acid to left forearm caused kicks in both 

 hind legs, but much more vigorous in the right. Also movement of left 

 forearm by itself, but weak. 



12.5. Acetic acid to left fore leg caused wriggling motion, first in right 

 hind leg and then in left fore leg in 16 seconds. Applied to right forearm 

 it caused a weak kick in right hind leg and wriggling in left hind leg, but 

 no motion in any other part. 



12.27. Acetic acid applied to forearm. No reflex action anywhere. 



12.30. No reflex action anywhere on application of acetic acid. 



12.30. Distance of coil 8. Electrodes in the spinal cord. Slight con- 

 tractions in right hind and left fore legs, and also in the abdominal 

 muscles, though very weak. It was now noticed that the cord with 

 which the frog was attached to the board had been very tightly tied 

 round the left forearm and left there. The circulation was stopped there, 

 as the cord had not been removed. 



The paralyzing effect of the poison on the motor nerves was here shown 

 by an involuntary experiment. On irritating the cord the ligatured leg 

 responded as we had expected, but we were astonished to see movements 

 in the left arm also. An examination of the limb at once showed the 

 cause of the phenomenon. The cord attaching it to the board had been 

 inadvertently drawn so tight as to obstruct the circulation, and thus pre- 

 vented the access of the poison to the nerves. 



Experiment XLI. 



May ]_5th. Bight thigh of frog ligatured, with exception of the sciatic 

 nerve. 



1.2. Ligature applied. 



1.4. A considerable dose of dried cobra-poison dissolved in water 

 injected into dorsal lymph-sac. 



2.26. Acetic acid applied to a limb causes no movement whatever in 60'. 



Interrupted current. Distance 0, electrodes in spine : only weak 

 twitch in muscles of forearms ; no movement in hind leg. 



2.30. Both sciatics exposed. 



Right sciatic. Distance 50, distinct contraction of gastrocnemius. 



Left sciatic. Distance 0, no contraction of gastrocnemius. Single 

 shocks. Both gastrocnemii exposed and irritated directly. 



YOL. XXII. I 



