626 



NERVOUS SYSTEM. 



pillow, he was under the necessity of holding the paralytic nostril open with the fingers, 

 in order to breathe freely." In the horse, the movements of the nostrils are essential to 

 respiration, the animal being unable to breathe through the mouth. When both facial 

 nerves are divided in this animal, the nostrils collapse and are occluded with each effort 

 at inspiration, and death takes place from suffocation. 



Sir Charles Bell and others have also noted an interference with olfaction, due to the 

 inability to inhale with one nostril, in cases of facial paralysis. The influence of the nerve 

 in the act of conveying odorous emanations to the olfactory membrane is sufficiently evi- 

 dent after what we have remarked concerning the action of the facial in respiration. 



The effects of paralysis of the other superficial muscles of the face are manifested in 

 the distortion of the features, from the unopposed action of the muscles upon the sound 

 side ; a phenomenon which is sufficiently familiar to the practical physician. When 

 facial palsy affects one side and is complete, the angle of the mouth is drawn to the 

 opposite side, the eye upon the affected side is widely and permanently opened even 

 during sleep, and the face has upon that side a peculiarly expressionless appearance. 

 When a patient affected in this way smiles or attempts to grimace, the distortion is 

 much increased. The lips are paralyzed upon one side, which sometimes causes a flow 

 of saliva from the corner of the mouth. In the lower animals that use the lips in pre- 

 hension, paralysis of these parts interferes considerably with the taking of food. The 

 flaccidity of the paralyzed lips and cheek in the human subject sometimes causes a puff- 

 ing movement with each act of expiration, as if the patient were smoking a pipe. 



FIG. 203. 



FIG. 204. 



FIG. 205. 



FIG. 206. 



FIG. 20T. 



FIG. 208. 



Expressions of the face produced by contraction of the muscles under electrical excitation. (Le Bon, after 



Duchenne.) 



Fig. 203, front view of the face in repose. 

 Fig. 204, profile view. 



Fig. 205, expression of laughter upon one side, produced by contraction of the zygomaticus major. 

 Fig. 20fi, expression of fear, produced by contraction of the frontal muscle and the depressors of the lower jaw. 

 Fig. 20T, expression of fear, profile view. 



Fig. 208, expression of fear and great pain, produced by contraction of the corrugator supercilii and the depressors 

 of the lower jaw. 



We have already seen that the buccinator is not supplied by filaments from the nerve 

 of mastication, but is animated solely by the facial. Paralysis of this muscle interferes 

 materially with mastication, from a tendency to accumulation of the food between the 

 teeth and the cheek. Patients complain of this difficulty, and they sometimes keep the 



