THE SYMPATHETIC SYSTEM 37 



is called vagotonic. In the same manner atropin paralyzes 

 the vagus and in sympathicotonic individuals will cause a 

 tachycardia, dilatation of the pupils, dryness of the mouth, 

 etc. This division of patients into vagotonic and sympa- 

 thicotonic has been further investigated during the last 

 few years. The oculo cardiac reflex is a great aid in this 

 respect. When positive, that is, when there is slowing 

 of the pulse after ocular pressure, it indicates vagotonia; 

 negative, that is, when there is an acceleration of the pulse 

 is considered to be a sign of sympathicotonia. In spite 

 of a certain reservation which we must make for this test 

 it is, nevertheless, a very useful sign whenever we are 

 investigating the sympathetic system. 



The study of the sympathetic is extremely fruitful and 

 complex and recent investigations indicate how much our 

 knowledge is increasing every day. It is, however, dif- 

 ficult to determine its limits. The nervous system of 

 vegetative life can be affected in many ways, often by the 

 intermediary of a gland of internal secretion. Actually, 

 as Dr. Guillaume has described, it consists of the true 

 sympathetic and the cranial and pelvic parasympathetic 

 system. It is in the cranial parasympathetic that we 

 must include the vegetative fibres annexed to the vagus 

 which exert their action on the respiratory system, the 

 gastro intestinal tract and its adnexa and the heart. It is 

 by the intermediary of these fibres that the association 

 reflex, such as, the oculo cardiac reflex occur. It is also 

 the case in these reflexes showing the connection between 

 the nuclei of the vagus and the general sensory tracts or 

 those showing the functional sympatehico-parasympathetic 

 mechanism. These examples show how many symptoms 

 can result from disturbances of the normal mechanism of 

 the sympathetico-parasympathetic apparatus. In the 



