1874.] Poison of Indian Venomous Snakes. 95 



Experiment XXXYI. 



A ligature was placed round the right thigh of a young frog, excluding 

 the sciatic nerve. 



2.42. A drop of dark fluid cobra-poison (the first supply) was injected 

 into the dorsal lymph-sac. Immediately after the injection the animal 

 became restless. 



3. It lies quietly with its eyes shut. It hardly moves when touched ; 

 but it struggles when laid upon its back. 



3.8. It can still draw up the ligatured leg. The other one can be 

 drawn up, but with a wriggling motion. "When laid on its back the 

 animal no longer resists. 



3.9.30. It lies quite flat. There is trembling of the leg when either 

 foot is touched ; and when it is pinched either leg can still be drawn up. 

 On suddenly touching the poisoned leg, the frog gave a jerk with both. 

 Respiratory movements have ceased. The exact time when they did so 

 was not noticed. 



3.17. The frog has become much lighter in colour, with the exception 

 of the ligatured leg. 



3.45. The eyes no longer shut when touched; they remain widely 

 open. Dilute acetic acid of 1 per cent, produces no effect when applied 

 to the sound leg ; but when the leg is lifted up, so as to prevent friction 

 against the table, it is drawn in towards the body. 



4.9. On applying a strong interrupted current to the eye of the frog 

 the unpoisoned leg jerks feebly, the poisoned one not at all. 



4.13. On turning the frog on his back the non-poisoned leg moved. 



4.20. Opened abdomen. The heart was beating, but only slowly. Irri- 

 tated the lumbar nerves on the left side (those of poisoned leg) by an in- 

 terrupted current. No contraction occurred in the poisoned leg; but 

 twitching took place in the non-poisoned one. Irritated lumbar nerves 

 of right side. Tetanus occurred in the right (non-poisoned leg). No 

 movement of the poisoned leg. Laid bare the muscles of both legs, and 

 irritated them by a Faradic current directly applied. Those of the poisoned 

 leg were paler than those of the other. The muscles of both legs con- 

 tracted when irritated directly. Exposed the sciatic nerves of both sides 

 and irritated them by an induced current. No contraction in the gastro- 

 cneinius of poisoned leg. Tetanus in the non-poisoned leg. 



4.35. The heart is no longer contracting. Electrodes were placed in 

 the medulla, and an interrupted current applied. Contractions occurred 

 in the non-poisoned leg. No contractions in the poisoned one. 



The movements which occurred in the non-poisoned leg when the 

 lumbar nerves of the other side were irritated, may have been due to re- 

 flex action through the spinal cord. If this were the case, it would indi- 

 cale that the sensory fibres in the lumbar plexus were not paralyzed, and 

 that the reflex power of the cord was not quite destroyed ; but the nerves 



