Ill \|M.\i;V OF CURRENT RESEARCHES RELATING TO 



[hick ii should be diluted with isotonic Ball solutions. After trying nu- 

 roufl fixatives and stains the author confined himself to two methods : 

 • ii with osmic acid or formalin, followed by one of the modifi- 

 mi- of the Romanowski stains: (2) fixation with Schaudinn's Bubli- 

 mate alcohol, followed by fleidenhain's iron-alum hematoxylin. When 

 using the former method the author proceeds as follows. A drop of the 

 medium containing the bacteria is placed on a slide, and then by it- side 

 a drop of 1 p.c. osmic acid or of pure formalin. The two drops are 

 mixed together and a film made. When dry the slide or slip is placed 

 in absolute alcohol for 10 to 15 minutes. On removal, it is allowed to 

 dry ami then stained with Giemsa or Leishman. After staining, the film 

 is differentiated in 30 p.c. alcohol, washed in distilled water, dried with 

 cigarette paper and mounted in cedar-wood oil or in neutral Canada 

 balsam. Chromatin structures are coloured a bright red, the cytoplasm 

 being blue, lilac or pink, according to the degree of differentiation. 



The author adds in a footnote that beautiful preparations of small 

 Flagellates and other protista may be obtained by the foregoing method. 



Rapid Staining with Giemsa's Azur-eosin Solution.* — G. Giemsa 

 gives the following method of using his azur-eosin mixture. Equal 

 quantities of the stock solution and methyl-alcohol are mixed. The 

 slide is placed coverside up on a Petri dish aud then covered with the 

 solution : this is allowed to work for half -a-minute. Distilled water is 

 then poured in until the slide is quite covered. The dish is then tilted 

 to and fro in order to mix the water aud solution. After 3 to 5 minutes 

 or even longer the fluid is decanted off, the slide washed in running 

 water, dried and examined in cedar-wood oil.. The author states that he 

 has not made sufficient trials to venture an opinion as to permanence. 



New Method of Chromatin Staining.!— Mentz von Krogh describes 

 the following easy method of staining chromatin ; it is specially adapted 

 for nervous tissue ; the only preparations for which it is distinctly un- 

 suitable are blood films. Paraffin sections are stained with Unna's'poly- 

 chrome methylen-blue for 5 minutes, aud after a short wash in tap-water 

 are mordanted from 1 to 15 minutes (according to the object dealt with) 

 m 2 p.c. chromic acid. After another wash the sections are differentiated 

 with 5 p.c. tannic acid solution until they assume a pale blue or a reddish- 

 violet hue. They are then washed anew, rapidly dehvdrated with abso- 

 lute alcohol, then .xylol and balsam. The chromatin of the cell-nucleus 

 should be dark blue, the protoplasm and its prolongations pale blue. 

 i bodies are blue, but not so dark as the nucleus; axis cylinders 

 wplel ; connective tissue is of a pale greenish hue. The stain is 

 suitable for showing up Negri's corpuscles. 



Saffron in Histological Technique.!— P. Masson has found that 



11 1 "ii has a remarkable affinity for collagen, staining it a brilliant 



As some samples stain the cell-protoplasm to a certain 



' isable to combine it with eosin and some nuclear stain, 



Muench. med. Wochenschr., 1910, p. 2476 

 Centralbl. Bakt., lte Abt. Orig., lviii. (1911) pp, 95-6. 

 I C.R. Soc. Biol. Paris, lxx. (1911) pp. 573-1. 



