144 Journal of Comparative Neurology. 



distal to the neck of the bladder. This fiber was traced out 

 with the aid of the camera lucida. In this ending twenty me- 

 dullated branches may be counted, almost every one of which 

 gives off one to several non-meduUated branches before losing 

 its medullary sheath and terminating. The area covered by 

 the branches of this nerve I estimate to be 1.4 mm. by .8 mm. 

 It should, however, be stated that only rarely is it possible to 

 obtain preparations which contain endings such as here sketched. 

 More often only a portion of such an ending seems stained or 

 a number of them overlap to such an extent that it is impossi- 

 ble to trace them individually. However, in the urethra, blad- 

 der, ureters, uterus (cat and rabbit), vagina, gall bladder 

 and bile duct, other gland ducts, and in the respiratory mu- 

 cous membrane of the nose, relatively large axis cylinders, 

 which could be traced through a varying number of division.? 

 have been observed by me, with now and then endings as large 

 or nearly as large as the one above mentioned ; although in the 

 bile duct and ureters I have never found such large endings. 

 That the majority of the branches of the larger medullated 

 nerves ending in hollow organs or gland ducts, are above the 

 muscular coat, I think my preparations show clearly. In the 

 one from which the accompanying figure was sketched, the 

 muscular coat had been dissected away before mounting the 

 preparation. Furthermore, as is well known, methylen blue 

 stains readily non-striated muscle, so that by focusing the ob- 

 server is usually able to make out the existing relations between 

 the nerve fibers and their branches and the muscular fibers 

 of the preparations under discussion. I do not, however, 

 wish to be understood as saying that the medullated nerve 

 fibers going to the hollow organs or gland ducts do not 

 branch external to, or in the muscular coat, for this is often 

 seen in suitable preparations, especially of the bladder wall and 

 gland ducts ; yet such branches can often be traced through the 

 muscular coat into the mucosa, where further and more fre- 

 quent division of the fibers is observed. 



It may be of interest to consider, at this point, this re- 

 peated division of the large, medullated visceral nerves in con- 



