POISON OF SOME INDIAN VENOMOUS SNARES. 77 



A minute or two afterwards a slight twitch was noticed in 

 one arm, to which acetic acid had been applied, but whether 

 this was greatly delayed reflex action caused by the acid, or 

 whether it was due to something else, is uncertain. A needle 

 was now run down the spinal cord. It produced no effect. 



The legs contracted readily when the lumbar nerves were 

 irritated. 



The absence of motion in the legs when the cord was irritated 

 by a needle run down the spinal canal shows that the power of 

 the cord to originate motor impulses had been destroyed, as it 

 would usually have caused violent contractions in the ex- 

 tremities. These, having been protected from the action of the 

 poison either on muscle or nerve, would respond readily, as, 

 indeed, they did, to voluntary motor impulses shortly before 

 the death of the animal. 



Experiment LI. 



May 12th, 1873. — The sacrum of a frog was removed, and a 

 ligature passed round the body, excluding the lumbar nerves. 

 There was a good deal of bleeding. 



12.30. Ligature tied. 



12.33. A good dose of dried cobra-poison dissolved in water 

 was introduced into dorsal lymph-sac. Immediately afterwards 

 the frog sprung about once or twice. 



1.27. Cornea insensible. On pinching the finger of either 

 hand it kicks out vigorously with tlie right hind leg. On 

 squeezing the toes of right hind foot it kicks out vigorously 

 with it. On squeezing toes of the left hind foot there is no 

 movement wliatever. On placing acetic acid on either foreaim 

 the frog kicks out strongly with the right hind leg. 



2. Interrupted current, distance 7. Acetic acid applied all 

 over the frog no longer causes any movement whatever. 

 Electrodes placed in spinal cord just below occiput. Cord 

 irritated by an interrupted current. Eight leg ki cksvigorously. 

 Ko motion in any other part of the body. 



Experiment LIl. 

 May 15th. — Frog ligatured round the middle, the lumbar 

 nerves excepted. A moderate amount of bleeding. 



