238 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
12. Sections parallel to the long axis of the sense cells demonstrate 
the existence of free-ending axis cylinders. 
13. Sections parallel, or nearly so, to the surface of the epithelium 
demonstrate that the nervous material is intercellular. 
VII. General Discussion and Conclusions. 
From the foregoing account it appears that in the ear, at least, we 
have a portion of the peripheral system in which the conditions are 
such as to furnish strong anatomical evidence in support of the neurone 
theory. "The absence of anastomosis between different axis cylinders, 
the distinctness of the sense cells, and the free terminations of the axis 
cylinders, support the validity of that view. ‘Though different authors 
have declared in a general way that anastomosis does occur, I am not 
aware that any investigator has maintained that the neurofibrillae of 
one axis cylinder are continuous with those of another, which I believe 
to be essential to a true condition of anastomosis. Retzius (:05>), 
who has given this subject more study than any other investigator, 
states that he has never seen cases of true anastomosis. 
The question whether free terminations exist or not depends upon 
what is meant by that term. Bethe and other adherents of the fibrillar 
theory oppose the doctrine of free nerve terminations. Dogiel (:05), 
who holds a modified form of the neurone theory, also disbelieves in 
their existence. ‘The opposition is based upon the affirmed existence 
of peripheral networks of neurofibrillae. ‘Thus Szymonowicz (’96) 
has described such closed terminal structures in Grandry’s corpuscles. 
Dogiel (:04) has recorded similar structures in the Herbst bodies. 
I have already (p. 217) stated Kolmer’s view, that the fibrillae of the 
eighth nerve have no free ends, but turn back at the periphery, forming 
loops, rings, er networks. If by free nerve terminations is meant the 
free ending of the neurofibrillae, and the maintenance of their indi- 
viduality to the periphery without anastomosis with one another, my 
preparations do not furnish conclusive evidence in the matter. But 
if by free ending is meant the maintenance of the individuality of axis 
cylinders, or branches of axis cylinders, to the periphery without 
anastomosis with one another or with other elements,— such axis 
cylinders being composed of a greater or smaller number of neurofi- 
brillae,— I cannot doubt that they are abundant in the region which 
I have studied. It is in this latter sense that the term is used by 
Retzius and other neuronists. Networks of neurofibrillae such as 
ae 
or tg = 
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