THE NERVO-VASCULAR SUPPLY OF THE LUNGS. 473 



the fact that, as in the latter, vagal and sympathetic fibers 

 are stated by all anatomists to form plexuses as they jointly 

 enter the lungs obviously suggests that these organs are on 

 the same plane in respect to our conceptions as any of the 

 thoracic viscera studied. So generally, in fact, have we found 

 this inosculation to mean combined and correlated function 

 that we have been led to believe that in all organs within the 

 vagal domain general motor functions invariably aim to pre- 

 serve tonic contraction of arteries and insure adequate nutri- 

 tion, while vagal functions are as universally intended to incite 

 and govern the active stage of these functions. 



Clinical evidence tends to sustain this view. It seems to 

 account, for instance, for the following results of section of 

 both vagi in the neck, as outlined by Sappey 33 : "Section of 

 both pneumogastrics in the median portion of the neck not 

 only abolishes the sensibility of the respiratory mucous mem- 

 brane and paralyzes the internal respiratory muscles; it also 

 involves as consequence a mucous effusion into the bronchi, 

 engorgement of the lungs, emphysema of these organs, and a 

 very sensible diminution in the number of inspirations/' In- 

 deed, the three functions we have ascribed to the vagus, sen- 

 sory, excitomotor, and vasoconstrictor (while its mate, the 

 general motor, only preserves tonic contraction during passive 

 function, and thus insures nutrition), are shown to actually 

 prevail by the results summarized in these few lines. If we 

 now carry this line of inquiry one step further, and recall the 

 sudden overwhelming effusions that sometimes appear in pneu- 

 monia, and also viewing the question from our standpoint 

 the vasodilating effects of declining oxidation processes of vagal 

 and general motor centers, due, in turn, to rapidly increasing 

 failure of adrenal functions, it will become apparent that both 

 systems must be concerned in vasoconstriction. Again, if the 

 anatomical coalescence of both sets of nerves into plexuses 

 here as elsewhere indicates correlated functions, the fact that 

 the sympathetic fibers do exercise vasomotor influence in the 

 lungs seems suggestive. 



The question as to whether vasomotor phenomena actually 



83 Sappey: "Traite d'Anatomie Descriptive," vol. iii, p. 397. 



