276 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Aiul for this purpose the mesentery of Triton cristatus is recommended. 
The smooth fibre requires a greater stimulus than the striated muscle. 
The difference between the contraction of the two varieties of muscle 
is merely one of manner and not of kind ; the striated muscle contracts 
quickly, the unstriped slowly. 
Examining the Endbulbs of the Frog.* — M. J. Fajerstajn demon- 
strates the termination of the nerves in the tongue and palate of the 
frog as follows. 
The fixatives used were chromic acid 1 to 400, sublimate 5 to 100, 
Kleinenberg’s solution, Flemming’s chrom-osmium-acetic acid, and 
Carnoy’s fluid (alcohol 6 vols., glacial acetic acid 1 vol., chloroform 
3 vols.). The sublimate and Flemming’s and Carnoy’s fluids were the 
best. The preparations were hardened in alcohol, and imbedded in 
celloidin or paraffin. 
For isolating the cylinder-cells the following method gave the best 
results : a mixture of 4 per cent, bichromate of potash and 1 per cent, 
chloral hydrate is made, and in it is placed either a piece of the palate 
mucosa, or the whole tongue, for 12 to 60 hours. The preparation is 
then placed under a dissecting Microscope, and teased out in a very weak 
solution of iodine-green. 
For staining sections, several procedures were followed, e. g. subli- 
mate 5 per cent., alcohol, paraffin, alum-carmine, with acetic acid and 
anilin-blue ; or Flemming’s mixture, alcohol, paraffin, methyl-green, 
metanil-yellow or the latter, preceded by safranin, Carnoy’s fluid, 
alcohol, paraffin, dahlia. 
Methylen-blue was used very satisfactorily for demonstrating the 
course of nerves. For this purpose it is advised to inject through the 
abdominal veins, as thereby the circulation is least interfered with. 
The injection must be done slowly, after paralysing with curara or 
anaesthetizing with ether. The solution used by the author was 1 part 
methylen-blue to 800 parts of a 0*6 per cent, chloride of soda solu- 
tion. 
Preparing Retrolingual Membrane of the Frog to show the 
junction of Muscular and Elastic Elements, and the natural termina- 
tion of Muscle Fibre.| — M. L. Ranvier was enabled to demonstrate the 
connection between the elastic and the muscular elements of the retro- 
lingual membrane in frogs by the following method. It was thereby 
found that the elastic fibres are attached to the sarcolemma, the two 
structures being welded together so intimately that mechanical means 
fail to break the continuity. 
The membrane taken from a pithed or decapitated frog is placed for 
24 to 48 hours in one-third alcohol. The epi- and endothelia are then 
removed with a brush ; after this the membrane is immersed for 24 hours 
in a weak solution of methyl-violet, 5B. The preparation is again 
washed and then mounted and examined in glycerin. 
Another histological problem was also resolved from this membrane. 
What is the natural termination of a muscular fibre ? Does it end in a 
thick disc, a thin disc, or in a clear space? By means of the following 
* Aroli. de Zool. Exper. et Gen., vii. (1889) pp. 705-50 (1 pi.). See Zeitsclir. f. 
AVibs. Mikr., vii. (1890) pp. 357 9. t Comptes Renclus, cx. (1890) pp. 504-8. 
