122 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
limate solution are well suited. Muller’s fluid cannot be used as it 
softens and disintegrates the masses of expectoration. 
The staining solutions employed by the author were alum-carmine, 
safranin, and hsematoxylin-eosin. By this method in three cases out of 
four examined, giant cells were demonstrated. 
Rapid Staining of Tubercle Bacilli in Tissue preserved in Muller’s 
Fluid.* — M. Letulle gives the following procedure for staining tubercle 
bacilli in tissues which have been hardened in Muller’s fluid. Accord- 
ing to this, and indeed other writers, Muller’s fluid is unsuitable as a 
hardening agent when these micro-organisms are to be sought for. 
After hardening in Muller’s fluid the material is treated with spirit 
and then imbedded in celloidin. The sections are then stained with 
haematoxylin and next with a rubin solution (2 per cent, carbolic acid 
water with rubin to saturation). The sections, after having been 
washed with water and alcohol, are further stained with iodine-green 
(iodine-green 1 grm., 2 per cent, carbolic acid water 100 grin). The 
preparations are then mounted in the usual way. 
The nuclei are stained violet, hyaline bodies rose, and the bacilli 
dark red, the rest remaining white. The whole procedure lasts barely 
half an hour. 
Hofmeister, F. — Ein Apparat fur Massenfarbung von Deckglastrockenprapa- 
raten. (Apparatus for Staining dry Cover -glass Preparations.) 
Fortschr. d. Med., 1892, pp. 531-6. 
C 5) Mounting-, including- Slides, Preservative Fluids, &c- 
Preserving Fluid and Fixing Material.f — Dr. F. Krasser recom- 
mends as a preserving fluid for vegetable substances a mixture of 1 vol. 
acetic acid, 3 vols. glycerin, and 10 vols. of a 50 per cent, solution of 
sodium chloride. In this solution sections of beet and of etiolated 
potato-shoots retained their structure and their colour for nearly a 
year. 
Salicy 1-aldehyde is a good fixing material for chromatophores, as e.g. 
the pigment of Solarium Lycopersicum. For this purpose Dr. Krasser 
uses a 1 per cent, alcoholic solution. 
Glycerin Mounting. J — Dr. C. E. McClung recommends the use of 
glycerin in the following : — “ The use of glycerin as a mounting 
medium is not as universal as its qualities merit it should be. The 
convenience with which a balsam mount is made proves a temptation 
which many microscopists cannot resist, and as a result, numerous 
mounts are entirely spoiled by consigning the object to a medium not 
adapted for its reception. There is a fitness in all things, and the 
saying is as apjDlicable to microscopy as to other departments of work. 
Balsam has its use and glycerin its application, and the two should be 
confined to their respective provinces. Frey says, £ What balsam is to 
dry tissues, glycerin is to moist ones,’ and the saying might be made 
even more emphatic. 
Glycerin has the advantage of being non-volatile, colourless, slightly 
* Gazette Hebd., 1892, No. 22. See Centralbl. f. Bakteriol. u. Parasitenk., xii. 
(1892) p. 441. 
t SB. K. K. Zool.-Bot. Gesell. Wien, May 20, 1892. 
X The Microscope, xii. (1892) pp. 201-3. 
