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4th. If instead of dividing entirely a lateral half of the spi- 

 nal cord, a small part is left undivided towards the centre of 

 that organ, the posterior limb on the same side becomes much 

 more sensible, but the posterior limb on the opposite side remains 

 very sensible and sometimes it appears more sensible than in the 

 normal state. 



5th. If in performing the section of a lateral half of the spi- 

 nal cord the instrument goes a little too far and divides also a 

 small portion of the other half, then the posterior limb on the 

 side of the complete section is less sensible than in the normal 

 state, and the posterior limb of the opposite side, loses com- 

 pletely its sensibility. 



6th. If the section of a lateral half of the spinal cord is made 

 at the level of the second or third cervical vertebra, it is found 

 that the sensibility becomes very quickly much greater in the 

 parts of the body on the same side as the section, and on the 

 contrary the parts on the other side becomes evidently less sen- 

 sible. 



7th. If after a section of a lateral half of the spinal cord at 

 the level of the eleventh costal vertebra, another section is per- 

 formed on the other side of that organ, at the level of the sixth 

 costal vertebra, so that the two lateral halves are divided, then 

 sensibility in most of the cases is lost, on both sides. Some- 

 times it retains a very slight degree of sensibility, more parti- 

 cularly in the posterior limb on the side where the spinal cord 

 has been divided at the level of the sixth costal vertebra. 



8th. If two sections of lateral halves are made as in the pre- 

 ceding experiment, but at a greater distance, one from the other, 

 on the right side for instance at the level of the twelfth costal 

 vertebra, and on the left side in the cervical region, nearly the 

 same results are obtained as to the posterior limbs, but the sen- 

 sibility is increased in the right anterior limb and it remains very 

 evidently, but much diminished, in the left anterior limb. 



9th. If a longitudinal section is made on the part of the 

 spinal cord giving nerves to the posterior extremity, so as to 

 divide that part into two lateral halves, then it is found that sen- 

 sibility is completely lost in the two posterior limbs, although 

 voluntary movements take place in them. 



10th. If a similar separation of two lateral halves of the spi- 



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