7/^ 



OBSERVATIONS ON THE INNERVATION OF THE 

 INTRACRANIAL VESSELS. 



By G. Carl Huber, 



Assistant Professor of Anatotny and Director of the Histological Laboratory in the 



University of Michigan, 



With Plate I. 



The research, the results of which are here given, was be- 

 gun some two years ago, at which time the only observations, 

 familiar to me, dealing with the innervation of the vessels of 

 the pia-mater and brain, were those of Lovell Gulland (i) and 

 Obersteiner (2). Gulland (i), at the suggestion of Dr. Batty Tuke, 

 examined the brain vessels, with a view of ascertaining "whether 

 it was possible to demonstrate nerve-fibrils in the walls of the 

 intracranial bloodvessels." "The methods employed were the 

 Golgi method with various modifications and the Ehrlich meth- 

 ylene blue method. The brains examined were those of cats 

 and rabbits, adult, young and embryonic and a number of hu- 

 man brains obtained as fresh as possible from the post-mortem 

 room." His results are summarized by himself as follows: 

 ' * The net result of all these observations was that neither by 

 the silver, the mercury, nor the methylene blue method could I 

 succeed in demonstrating any nerve-fibers in the walls of the 

 pial vessels nor of the intracerebral vessels. In Golgi prepara- 

 tions, the bloodvessels, especially the smaller ones, are often 

 impregnated as a whole ; sometimes a partial impregnation of 

 this sort gives an appearance like a nerve plexus. Again in 

 the larger vessels especially, the longitudinal network of elastic 

 fibers is often impregnated, but it is easy to distinguish this 

 from the nerve plexus of ordinary arteries. The processes of 

 the neuroglia cells attached to an artery and running along it, as 

 they often do, for a little way, might also give rise to error." 



