384 
B. MELLAND. 
“ fixed waves of contraction/’ described in the osmic acid 
preparations. 
In a preparation of fresh muscle I have seen a fibre undergo 
slow rigor mortis, commencing at one end and gradually ex- 
tending towards the other. It exactly resembled a very slow 
contraction wave passing over the fibre, and the changes 
undergone by successive discs, as the contraction affected them, 
were similar in appearance to those described in fig. 18, and 
could be observed with more deliberation than usual. 
The Fibre under Polarised Light. — The effects observed 
in the living fibre with crossed Nichols were exactly similar to 
those figured and described by Briicke and Schafer Quain’s 
Anat./ 9th ed., vol. ii, fig. 125). Briicke’s drawing is almost 
identical with diagram 3. 
The fibre is chiefly made up of doubly refractile or aniso- 
tropous material, but a band of singly refractile or isotropous 
material crosses the fibre transversely in the position of each 
Krause’s membrane, and this band is seen with a high power 
to consist of a row of rhomboidal dots. Fine lines of isotro- 
pous material are described running longitudinally across the 
anisotropous discs and joining the rhomboidal dots. The 
appearance of the muscle-fibre under polarised light leads us 
to the belief that the network consists of isotropous, the matrix 
or ground substance of anisotropous or doubly refracting 
material. 
V. Alcohol Preparations. 
Alcohol preparations of muscle show, in most cases, a some- 
what different character to those prepared by the preceding 
methods. 
Spirit has a tendency to split the fibre into fibrils and sarcous 
elements. After the muscle has been in alcohol it may be 
stained with some reagent; Kleinenberger’s hsematoxylin, for 
instance, gives excellent results. Alum carmine may also be 
used. Mount in Canada balsam. 
Absolute alcohol has a somewhat different effect from 
ordinary spirit. It sometimes seems to fix the fibre as 
