DR. BEALE, ON NERVE-FIBRES AND CELLS. 101 
cular fibre, the nuclei are seated in the substance of the con- 
tractile substance. The nerve-fibres do not penetrate through 
the sarcolemma, but always lie on the surface, where they 
divide and subdivide, forming networks of very fine fibres, 
many of which (although much finer than the fibres delineated 
by Kiihne in his drawings) can be traced over several ele- 
mentary muscular-fibres. It is most unsatisfactory, and, at the 
same time, surprising to find that these three authorities in 
microscopical anatomy have been led by studying the same 
object to conclusions so incompatible with each other. This, 
however, occurs not unfrequently in all investigations of 
natural things, and we believe that it arises from two causes. 
The first, that the minds of individuals are differently consti- 
tuted, so that when two observers investigate one object 
they do not view it in the same manner; the second, that 
the same object prepared in various ways exhibits under 
microscopical examination different appearances. To the 
latter, rather than to the former cause, we are inclined to 
ascribe the different conclusions arrived at in the present 
instance; and we believe that had the observers examined 
one object always under the same conditions we should 
not have to complain of so many terrible discrepancics 
which at present complicate histology. It is of great im- 
portance in microscopical investigations to prepare the object 
in such a way, that while we are endeavouring to find out 
the structure and render the appearances distinct, so as to 
demonstrate them to others, we should preserve, as far as 
possible, their natural appearances. With regard to the ex- 
amination of the ultimate arrangement of nerves in different 
parts of the body, we think that Dr. Beale’s method of pre- 
paring is one of the best, for it alters, as little as possible, 
the delicate structure of nerves at their termination. We 
have had many opportunities of using this method, and 
always with great success. We, therefore, highly recommend 
it to those who are engaged in this kind of research; and 
it should be borne in mind that in preparing all the tissues 
of vertebrate animals, Dr. Beale employs the same method. 
Not only so, but the appearances described by him in many 
of the lower plants and animals, were observed in specimens 
prepared by the same general plan. 
We shall now proceed to describe briefly the principal and 
most interesting specimens which were sent round during 
the lectures. Every specimen has been carefully examined by 
us, and we feel convinced that the description given is sup- 
ported by irrefragable facts. 
Prep. 1.—Bundle of pale, gray, or gelatinous fibres with 
