308 



ARRANGEMENT OF NERVE-FIBRES TO CAPILLARIES. 



I am sure that they exist, and in considerable num- 

 ber. The tissues of man and the larger mammalia 

 are very unfavourable for so delicate an investigation, 

 in consequence of the very diaphanous character of 

 their nerve-fibres and the great density of the con- 

 nective tissue in which they are embedded, but in the 

 mouse, shrew, mole, and some other small animals, 

 they may be distinctly seen in very thin preparations. 

 More recently I have obtained some most excellent 

 preparations from the bat's wing. In these, nerves 

 to the capillaries may be demonstrated conclusively 

 with the aid of a yV^b. The -^Vth brings them out 

 still more clearly. In the preparation I showed at 

 the Microscopical Society, which was placed under 

 the twelfth of an inch object glass, many dehcate 

 nerve-fibres could be seen with great distinctness 

 running very close to almost every one of the capillary 

 vessels. In order to demonstrate this fact, it is 

 necessary to remove the dark cuticular covering from 

 both surfaces of the membrane of the wing — an 

 operation by no means easy, nor always followed by 

 success. 



307. Arrangement of the nerve-fibres distributed 

 to tJie caiiillaries. — With regard to the general 

 arrangement of these delicate nerve-fibres, it is to be 

 remarked that in many instances a fibre may be seen 

 running on each side of a capillary vessel. The two 

 fibres are often connected by short branches which 

 pass over or under the vessel. Plate XVI, figs. 1, 2, 

 3, Plates XVIII, XIX, and XX. 



Wot unfrequently the nerve is so close to the 

 capillary that it cannot be seen distinctly in all parts 

 of its course, but oftentimes the capillary shrinks 

 after death, and then a distinct interval is left between 

 its walls and the nerve-fibre (Plate XIX, fig. I). In 

 some cases the nerves are still more numerous, and 

 in the bat's wing I have seen three or four very fine 

 fibres ramifying over a capillary for a short distance. 



