POISON OF SOME INDIAN VENOMOUS SNAKES. 75 



The muscles of the ligatured leg respond to the direct appli- 

 cation of electricity more freely than the other muscles. 



In this experiment the poison employed had not been 

 coagulated or dried, and the dose was somewhat small. The 

 failure of retlex action while voluntary motions still continued 

 in the nerves shows that the cord in this instance became 

 paralysed before the motor nerves. It is, indeed, difficult to 

 say whether the motor nerves were paralysed in this case or 

 not, as the muscles themselves were distinctly weakened. 



Experiment XLIX. 



December 1st, 1872. — The right leg of a frog was ligatured, 

 excluding the sciatic nerve, which was kept covered by a flap of 

 skin to prevent its becoming dry. A ligature was also put 

 round the left leg in a similar manner, but not tightened. 



2 P.M. Cobra-poison injected into the abdominal vein. 



The effect not being marked, the aorta was exposed. 



2.27. Some poison injected into the aorta. It seemed to 

 take effect at once ; all motion ceased immediately. 



2.30. The ligature was then tightened round the left leg. 



2.48. The frog has since moved, but all motion has now 

 ceased. 



2.52. Even when irritated by acetic acid there is no move- 

 ment. The heart is still contracting. 



No reflex action occurs when a strong interrupted current is 

 applied to the nose or limbs. 



Lumbar nerves exposed and irritated. 



Eight. Distinct contraction of thigh. Coil at 58*5. 



Left. „ „ „ „ 58-5. 



Eight. Distinct contraction of whole leg. Coil 50. 



Left. „ „ „ „ 50. 



Sciatics exposed and irritated. 



Eight. Contraction. Coil 77. 



Left. „ „ 52. 



3.28. Eight. Contraction. Coil 50. 

 Left. „ „ 43. 



The poisoned leg seems to be losing its irritability more 

 quickly than the other. Irritability of spinal cord gone. 



