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PROFESSOR BEALE’S NEW OBSERVATIONS UPON THE 
The Nerves. 
With regard to the trunks of the nerves, I remark the following facts of im- 
portance : — 
1. That the bundle of nerve-fibres distributed to a papilla always divides into two 
bundles which pursue opposite directions. The division of the bundle may take place 
just at the base of the papilla, or at some distance from it, hut it always occurs (Plate 
XXI. fig. 1). 
2. Fine pale nerve-fibres pass from the same trunk of dark-bordered fibres as that 
which gives off the bundle of nerves to the papilla. The fine fibres ramify — 
a. Amongst the muscular fibres of the tongue (Plate XXI. figs. 1, 9). 
h. Upon the vessels (Plate XXI. fig. 1, i, i, i). 
c. In the connective tissue of the tongue generally, and also in the simple papillae 
(Plate XXI. fig. 1 ,d,e). 
The division of the bundle at the base of a papilla is shown in Plate XXI. fig. 1, and 
in Plate XXII. fig. 10 is a diagram to indicate the manner in which the nerve-plexuses 
at the summits of the papillae are connected together by commissural fibres. Thus in 
action the papillae may be associated together. The bearing of this arrangement upon 
the existence of complete nervous circuits is discussed in my ‘ Archives,’ vol. iv. The 
bundle in the central part of the papilla consists of dark-bordered fibres, which frequently 
cross and interlace with one another in this part of their course. They vary much in 
diameter, some being so fine as scarcely to be visible. 
As the bundle passes towards the summit of the papilla, the individual fibres divide 
and subdivide into finer branches. Now, as I have before remarked, nerves so near 
their distribution as these do not usually possess an axis-cylinder as a structure distinct 
from the white substance. The white substance does not abruptly cease, while the axis- 
cylinder is alone prolonged onwards by itself as is often described, but the entire fibre 
divides and subdivides. In fact dark-bordered nerve-fibres, near their ultimate ramifica- 
tions, always consist of fatty albuminous material imbedded in a transparent matrix of 
connective tissue. The “tubular membrane,” “white substance,” and “axis-cylinder” 
can never be demonstrated as distinct structures near the peripheral distribution of 
nerves. The “ tubular membrane ” is nothing more than the transparent matrix in 
which one or more nerve-fibres are imbedded. 
The dark-bordered fibres divide into finer fibres about the level of the ring or half-ring 
of capillaries at the summit of the papilla. As the fibres are exceedingly transparent, 
they are usually lost from view about this point. For example, Hartmann’s figures 
convey the idea that distinct dark-bordered fibres can be followed as high as this point, 
but that they cannot be traced further. Above this spot the papilla is a little thickened 
and the tissue more granular, and hence it is not to be wondered at that great difficulty 
should have been experienced in demonstrating the further course of the nerves, or that 
many different views should be entertained upon the oft debated question of the mode 
