Histology. — "On the Regeneration of Sensitive End-corpuscles 

 after section of the nerve". By Prof. J. Boeke. 



(Communicated at the meeting of September 30, J 922). 



During the process of regeneration of the motor endplates of 

 striated muscles we are in a position to observe not only that the 

 nerve-fibers put forth new shoots again and unite with the muscle- 

 libers to form new end-pla(es, but also that all the surrounding 

 tissue elements: the connective tissue as well as the muscle-fibers, 

 the nerve-sheaths and (he axis-cylinders of the nerves themselves, 

 play a part in the regeneration process and are instrumental in 

 ensuring its success. 



In the case of sensitive nerve-endings it is more difficult to observe 

 this procedure: 1° because there is a greater variety in the shape 

 of these endings than in that of the motor end-plates, 2" because 

 many more varieties occui- side by side in the same environment, 

 and 3° because sensory endings generally offer greater difficulty in 

 establishing the relation between the nerve-fibers and the surrounding 

 cells than motor end-plates do. 



Now in the cere of the duck's bill there are two sorts of 

 sensory end-bodies, viz. those of Grandry and Herbst, which are 

 very well adapted to such an investigation by their simple, well- 

 defined structure. 



We examined the regeneration after cutting the nerve. The ope- 

 ration was well sustained by the animals and in a short time the 

 wound was healed in primam (among 24 cases one inconsiderable 

 suppuration) without any injury to the animals. 



After 4 — 5 days the severed nerves were completely degenerated ; 

 nothing was left of the axis-cylindei- except a few granules staining 

 brownish black by Bielschowky's method. After some days these 

 also disappeared. 



An alteration of Grandry's tactile cells or of Herbst's core-cells, 

 described by Gasiorowski years ago after cutting the nerve, consisting 

 in shrivelling of the cells and bulging and wrinkling of the nuclei, 

 T have not been able to detect. In agreement with the aspect of 

 the soles of the motor endings the protoplasm became more coarse- 

 grained, swollen, while the impression was given that in the core 



