PHYSIOLOGY OP GLANDULAR SECRETION. 265 



nerve, therefore, is, according to our view, nothing but a motor 

 nerve distributed to the muscular coat of the vessel. Does this 

 also apply to the vascular supply of the internal organs? We 

 have ascertained that the existence of the vasomotor nerves 

 in the parts studied was purely inferential. If works on 

 anatomy are consulted i.e., works in which actually-present 

 structures are described no reference to a special set of nerves 

 endowed with vasomotor functions is made. The subdivisions 

 of the sympathetic are deemed to be the vasoconstrictors; as 

 to the vasodilators, apart from those distributed to the sub- 

 maxillary and parotid glands, the tongue and the auricles, all 

 still belong to the domain of conjecture. 



If our view is based on a solid foundation, we must, 

 however, be able to show that all the nervous structures com- 

 prised under the name of "sympathetic" are component parts 

 of the general motor system and that they are not only capable 

 of causing constriction, as now generally believed, but also 

 dilation of the structures to which they are distributed. We 

 have seen, for example, that when the cervical sympathetic 

 chain is severed, the phenomena are those already referred 

 to dilation of the vessels of the ear, which can be overcome by 

 stimulation of the cephalic end of the cut nerve. We must also 

 account for the phenomena witnessed at least as well as they 

 are by the older doctrine. In this experiment it is plain that 

 the dilation of the vessels ensues owing to the kss of their 

 regulating nerve-impulse. The fact that the local temperature 

 rises shows that the oxidation process is independent of the 

 impulse, since it continues nevertheless. On the electric cur- 

 rent being applied the nerve-impulse is replaced, the re- 

 contracted vessel overcomes the exaggerated blood-flow, and 

 normal conditions are restored. Of course, we shall have to 

 introduce various phenomena, now attributed to the sympa- 

 thetic nerves, which belong to the domain of the suprarenal 

 glands and perhaps to the other organs of the system described 

 in the last chapter, since it is only by clearly defining the part 

 taken by each set of organs involved that we can, if not 

 elucidate the subject itself, at least make our position clear. 



We are fortunate in having at our disposal in this con- 

 nection the article, previously referred to, by B. Onuf (Onu- 



