706 HUBER. [Vol. XI. 



14 and 15) just below the central wound, no axis cylinders 

 were seen ; one meets only the degenerated fibres shown in 

 PL XXXIV, Fig. 7. This, together with the fact that there 

 are no elements in the connective tissue (if our conception of 

 the structure of the axis cylinder is correct) from which the 

 few axis cylinders there found might have been developed, 

 would, I think, justify the assumption that they are buds from 

 the central axis cylinders ; although, in my preparations, I am 

 not able to make out a connection between the axis cylinder 

 of the central fibre and the axes found in the connective tissue 

 just below. 



At thirty-nine days after the implantation new axis cylinders 

 are found in the implanted segment, in the peripheral wound, 

 and in the central end of the peripheral ulnar. When sections 

 of the central wound are compared with the ones made from the 

 same region of a nerve removed twenty-one days after implan- 

 tation, a very much larger number of axis cylinders is evident 

 in the connective tissue uniting the central ulnar and the 

 implanted segment. Here some are found arranged in small 

 bundles, others are disposed singly. The bundles and single 

 fibres are often seen deviating from a course parallel to the 

 axis of the nerve. They can be traced above into the central 

 stump, and below into the implanted segment. The deeply 

 stained axis cylinders are surrounded by a narrow border tinged 

 faintly blue. Long, rod-shaped nuclei with rounded or beveled 

 ends are observed in the pale blue layer, closely applied to the 

 new axis cylinders. In cross-sections of the implanted segment, 

 about I ctm. below the central wound, a small portion of one 

 of which is reproduced in PI. XXXIV, Fig. 9, the degenerated 

 fibres of the implanted nerve are seen as small, oval, or round 

 tubes, the wall of which is formed by the old sheath of 

 Schwann, containing a homogeneous protoplasm which scarcely 

 stains. In a few of the collapsed fibres a nucleus is observed. 

 This section presents an appearance differing from a cross- 

 section of a degenerated nerve trunk at a similar stage, in the 

 large amount of connective tissue found between the fibres. 

 This connective tissue, which, as far as my observation goes, 

 always develops around and between the elements of the 



