566 MICROSCOPY. 
the Royal Microscopical Society and to the Memoirs in the Quart. 
Journ: of Microscopical Science. Interesting incidental discus- 
sions may be found in the Proceedings of the Royal Microscopical 
Society in recent numbers of the Monthly Microscopical Journal. 
Dr. Beale, in reporting his progress on this subject, offers no 
methods of investigation, different from those already published, _ 
but hopes for improvement in practical details, and consequently 
inresults. He has demonstrated the distribution of nerve fibres to 
capillaries in nearly all the tissues of the frog, and is convinced of 
their similar arrangement in the higher animals. These delicate 
nerye fibres are seen to branch directly from the dark-bordered 
nerve fibres, and are often so close to the capillary as to be seen 
distinctly only when the vessel shrinks after death; and they may 
often run along on each side of the vessel, or form a plexus 
upon its surface. They may originate from ganglia or from sensi- 
tive and motor nerve, trunks, and have intimate relations to some 
of the nerves of special sense, and to nerve fibres distributed to 
the voluntary muscles. They never, according to the author's 
observations, come into structural relation with the active elements 
of other tissues, notwithstanding the growing belief that they do 
so; and their influence is not dependent upon continuity of sub- 
stance. The author is quite certain that muscular contraction may 
. depend upon changes in a nerve running near the muscular fibre 
but distinctly separated from it. A nerve fibre often passe for 
some distance by the side of a cell and then is lost to view by - 
passing behind it, or is hidden by a pigment cell, leading to the 
conclusion that the nerve fibre has become continuous with he 
substance of the cell. Such errors can be avoided only by study- 
ing extremely delicate specimens in a viscid fluid in which ter 
position can be changed; hence the author’s preference for glye 
erine as a medium for these investigations. A fine nerve so : 
less than zosbe0 Of an inch in diameter may often be traced for 8 : 
long distance, its edges being well defined, and nuclet occurring 
at certain intervals. These fibres, demonstrated by 
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plexuses. He admits that these are sometimes, and pro ey 
always, compound fibres, but does not ad 
another plexus of far finer fibres as claimed by some 
ers, preferring to discuss the bearing of what he has 
