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SUMMARY OF CURRENT RESEARCHES RELATING TO 
Staining Motor Nerve-endings in Striated Muscle.* — Sig. C. Negro 
bas devised a method for simultaneously staining and fixing muscle, 
especially suitable for demonstrating the nerve-endings in the mus- 
cular tissue of Reptilia. The solution is made of saturated solution of 
ammonia-alum, 150 ccm., and saturated alcoholic solution of hemato- 
xylin (Grubler) 4 ccm. This mixture is exposed to the air for eight 
days in an open vessel and then 25 ccm. of both glycerin and methyl 
alcohol are added. 
The procedure is as follows. The insertion of the muscle is teased 
out on a slide, and when this has been sufficiently done some drops of 
haematoxylin solution are added to it. In 15 to 20 minutes it is care- 
fully washed while on the slide and then mounted in a mixture of 
equal parts of glycerin and water. Put up in this way the preparation 
will keep for at least two years. 
Another method consists in overstaining and afterwards decolorizing. 
This is done by immersing separated muscle fibrils in the hrematoxylin 
solution for 24 to 48 hours, anil after washing, to keep the preparation 
in the glycerin and water until required. The fibril is then teased 
out on a slide, and if overstained it is treated for 10 to 12 seconds with 
the following mixture ; — Glycerin 40 parts, hydrochloric acid 1 part, 
distilled water 20 parts. 
A too prolonged action of the acid fluid decolorizes the nerve- 
endings and also affects their structure. 
Rapid Staining of Elastic Fibres.t — Sig. E. Burci gets very 
satisfactory results by using aurantia di-trinitrophenylamiue 
toxylin, are washed in water, dipped for one or two minutes in a 
saturated alcoholic solution of aurantia, washed in absolute alcohol, 
cleared in clove oil, and mounted in balsam. 
New Method of Double Staining. :f —Sig. Pianese proceeds by first 
preparing Martinotti’s solution, a saturated solution of picric acid and 
nigrosin in alcohol Two parts of this solution and one part of anilin 
water are next mixed and allowed to evaporate in .the open air. From 
this are deposited crystals which are dissolved in absolute alcohol. 
From the latter arc obtained cubical crystals of an olive green colour, 
soluble in water, alcohol, or ether. With these crystals are made a 
2 per cent solution in spirit for tissues, in water for micro-organisms. 
The sections are first stained either with Beale’s carmine or Orth’s 
lithia carmine, and having been treated with acidulated alcohol, are 
washed and then dehydrated. They are now immersed from two to ten 
minutes in the alcoholic solution of picro-nigrosin until they assume a 
brown hue. They are next decolorized in an alcoholic solution of oxalic 
acid, dehydrated, cleared up and mounted. 
By this method the nuclei are stained red, the plasma is a dark 
* Bn]], dei Musei di Zool. ed Anat. Compar. della R. Unio di Torino, v. (1890). 
See Bull. Soc. Beige de Mieroscopie, xviii. (1891) pp. 9-10. 
t Atti Soc. Tosc. Sci. Nat., vii. (1891) pp. 251-3. 
X La Riforma Medica, 1890, No. 155. See Bull. Soc. Beige de Microscopic, 
xliii. (1891) pp. 13-11. 
The sections, stained with carmine or liasma- 
