8 Transactions of the 



and specimens in which four, or even five excessively delicate nerve 

 fibres diverge from a mass of bioj^lasm with as many angles is occa- 

 sionally met with. Thus, as in other situations, lax networks are 

 formed, the meshes of which are for the most part long and narrow. 



Central Origin and Peripheral Connections of Nerve Fibres 

 distributed to the Capillaries. 



As regards the origin and connections of nerve fibres ramifying 

 upon the capillary vessels I have some important facts to record. 



1. In many instances, particularly in the fibrous membrane 

 about the bladder of the frog, I have followed fine nerve fibres 

 from ganglion cells to the smallest arteries, where they form a 

 plexus from which pass branches direct to the capillaries. 



2. I have traced nerves direct from the ganglia embedded in 

 connective fibrous tissue to the capillaries. See Plate V., Fig. 3. 



3. A specimen under the microscope this evening proves that a 

 fine nerve fibre given off from a bundle of dark-bordered fibres 

 distributed to voluntary muscle may be followed direct to a capil- 

 lary. See Plate IV., Fig. 3. 



4. From the ganglia between the muscular and mucous coats 

 of the small intestine of any small animal (mouse, mole) fine nerve 

 fibres can be followed in considerable numbers, and traced to the 

 capillaries of the mucous membrane. I have never been able to 

 see them on the vessels of the villi, but feel convinced they are to 

 be demonstrated as far as this point. Even in the human subject 

 I have succeeded in making some good, but not perfectly demon- 

 strative specimens. 



5. "I have seen a dark-bordered nerve fibre divide into two 

 branches, one of which ramified upon an adjacent vessel, while the 

 other was distributed to the elementary fibres of the muscle." 

 Also "nerves distributed to arteries and to elementary fibres of 

 striped muscle have been seen to be derived from the same trunk 

 of dark-bordered fibres." * 



With reference to the peripheral connections of nerves distri- 

 buted to capillaries, I have to remark — 



1. That in the papillae of the frog's tongue, I have followed 

 fibres from the expansion of the sensitive nerves above the capillary 

 loop to the caj)illary vessels, and also from a somewhat similar 

 structure in the mucous membrane of the snake's mouth to the 

 capillaries. In both cases fibres are also given off" from the bundles 

 of dark-bordered fibres before they break up to form the reticulated 

 sensitive expansion. 



2. The bundles of sensitive fibres which break up and form 

 expanded networks in the meshes of the beautiful capillary net- 



* Croonian Lect., 'Proceedings of the Eoyal Society,' May 11th, 1865. 



