108 PROGRESS OF MICROSCOPICAL SCIENCE. — [jouthis Microscopml 
his several observations on Rotifera. Many very interesting and novel 
facts are recorded, but the nature of the ciliary movement is still 
practically left unsolved. 
New Mode of Sub-stage Illumination.—Dr. J. Matthews has devised 
a plan for this purpose which has been very favourably spoken of. It 
consists in the employment of a low-power object-glass so fitted that 
the pencils proceeding from it may be thrown at any angle on the 
object. Dr. Matthews has solved the difficulty of sub-stage ilumina- 
tion by adopting one of the objectives themselves, of lower power, as 
an illuminator in place of a condenser, but not axially. It must be 
so mounted as to send the whole of its bundle of rays at angles vary- 
ing with the requirements of any given case, and in this consists the 
value of the method. Any of the powers may be used, bearing in 
mind that the higher the examining, the lower, within convenient 
limits, should be the illuminating power, in order to secure a propor- 
tionate amount of light. The only use of condensers of short foci 
and wide angle is to get the more oblique rays of the cone by stop- 
ping out some part of the rest. Dr. Matthews’ best results have 
been procured by a 2rds or 14 object-glass, which gives in all cases quite 
sufficient light. ‘There is no limit for the angle at which the illumi- 
nator may be used in relation to the axis of the instrument short of 
90°, supposing both the covering and the mounting glass as well as 
the stage to be of no thickness; but as they all have a very sensible 
one, and it is found that rays of a greater angle than about 83° do not 
pass through the slide to the object, but are reflected and lost, he has 
found it better to work at angles varying from 25° to 65°.—See 
Journal of Quekett Club, July. 
How Motor-nerves end in Non-striated Muscular Tissue-—A very 
valuable communication stating the results of M. Hénocque’s researches 
has been published in the ‘ Archives de Physiologie’ (May), and may 
be thus abstracted :—1. The distribution of the nerves in smooth 
muscle is not only identical in man and other vertebrate animals in 
which it has been observed, but is essentially similar in all the organs 
containing smooth muscle. 2. Before terminating in the smooth 
muscles, the nerves form three distinct plexuses or networks—(a) a 
chief or fundamental plexus, containing numerous ganglia, and situ- 
ated outside the smooth muscle ; (b) an intermediate plexus ; and (c) an 
intra-muscular plexus, situated within the fasciculi of smooth fibres. 
3. The terminal fibrils are everywhere identical; they divide and sub- 
divide dichotomously, or anastomose, and terminate by a slight swell- 
ing or knob, or in a punctiform manner. The terminal swelling 
appears to occupy different parts of the smooth muscular fibre, but 
most frequently to be in the neighbourhood of the nucleus, or at the 
surface of the fibres, or, lastly, between them. The methods of in- 
vestigation adopted by M. Hénocque have been very numerous, in- 
cluding the maceration of the preparations, obtained in as fresh a 
condition as possible, in aqueous humour, artificial serum, pyroligneous 
acid, chromic acid, chloride of gold and potassium, especially the 
latter, in a strength of 5},th. 
