398 Dr. C. S. Sherrington. Experiments on the Value of 



well opened, and the pupil distinctly dilated in the paroxysm of 

 anger. Since the brain had been by the transection shut out from 

 discharging impulses via the cervical sympathetic, the dilatation of pupil 

 must have occurred by inhibition of the action of the oculomotorius 

 centre. That the cervical sympathetic had been cut off from its normal 

 bulbar and cerebral excitation was shown by the semi-paralysis of the 

 membrana nictitans in this dog, as in all the others, after cervical spinal 

 transection. This partial closure of the eye, due to impaired tonus in 

 the third eyelid, was little if at all diminished during the outburst of 

 rage ; but we sometimes thought that during the fit of anger the third 

 eyelid was a little more retracted than in its usual paretic condition. 



As in the other dogs after spinal transection, so in this, the spinal 

 transection markedly enfeebled the voice. This we thought traceable 

 entirely to the enfeeblement of the respiratory muscles, the only respi- 

 ratory muscle left unparalysed after the transection being the diaphragm. 

 The viciousness of the enfeebled and short-winded growl and bark 

 remained as unmistakable and virulent as ever. Apart from this 

 change in the ocular and vocal factors of the facial and respiratory 

 expression of anger, we detected no departure from their previous 

 normal in any direction whatsoever. The heart-beat could be felt 

 to be altered, sometimes becoming quick and sometimes slow, but 

 rarely remaining unchanged during the exhibition of wrath. I thought 

 I could feel " mgus heats,^^ but the upset of respiratory movement made 

 the judgment difficult. 



One hundred and eighty days after the spinal transection, I divided 

 imder deep chloroform anaesthesia the right vagus nerve in the neck, 

 about the level of the cricoid cartilage, and therefore well below the 

 superior laryngeal branch, but above the recurrent laryngeal. The 

 cervical sympathetic trunk in the dog is contained in the same sheath 

 as the vagus, so also is the depressor branch of the superior laryngeal,, 

 and all three were divided by the same section. This operation pro- 

 duced curiously small obvious result. There ensued little or no 

 difference between the pupils ; the right was generally a little the 

 smaller. Absolutely no difference was discoverable between the degree 

 of protrusion of the third eyelids right and left. The palpebral open- 

 ings on the two sides appeared the same. The pose of the pinna of the 

 ear of each side, both right and left, seemed quite similar. The 

 voice, after the first day succeeding the operation, when it seemed 

 altered in some quality difficult of description, reassumed the char- 

 acter it had had since the spinal transection. The exhibition of 

 emotion, as tested by delight, anger, and fear, indicated emotional 

 states as marked and violent as ever. The trauma was rapidly 

 recovered from as legards the healing of the small wound necessary. 



Twenty-eight days later the left vagus nerve was similarly divided 

 under deep anaesthesia, and at the same level as the right. The left 



