110 SUMMARY OF CURRENT RESEARCHES RELATING TO 



will have adhered to the underlay. Should special care be demanded 

 the section may be placed for a few minutes in 10 p.c. formalin, or 

 exposed to action of formalin vapour in a closed vessel. 



The further treatment of the sections is the ordinary one : there is 

 no fear that the sections will fail to adhere. Paraffin sections are treated 

 in a very similar way. Frozen sections are also amenable to this fixation 

 method. The sections are taken off the knife and transferred to a 

 solution of the gelatin and water (1-10), and then placed on a slide. 

 The preparations are then exposed to the action of formalin vapour in a 

 closed vessel. After at least one hour the preparations are immersed in 

 10 p.c. formaUn. The subsequent treatment is the usual for frozen 

 sections. 



Similar devices have been suggested by Koninski* and by Bolton 

 and Harris.t 



(4) Staining- and Injecting. 



Staining Bacteria in Sections.^ — Saathoff advises the following 

 method for staining bacteria in sections, whereby, in a blue and reddish 

 stained tissue, the organisms are stained deep red, nuclear membrane and 

 network appear blue, nuclear granules and protoplasm red. Methyl 

 green 0'15, pyronin 0*5, 96 p.c. alcohol 5*0, glycerin 20, and 2 p.c. 

 carbolic acid water to 100. Stain for 2-4 minutes, wash with tap water 

 until the green colour changes to bluish red, wash in absolute alcohol, 

 clear for few seconds in xylol, and mount in balsam. 



Carmin Staining of Glycogen and Nuclei.§ — F. Best used celloidin 

 sections, and did not remove the imbedding medium, as this pre- 

 vented the glycogen from being dissolved out in water. The staining 

 solution was composed of : cannin 2, potassium carbonate 1, calcium 

 chloride 5. These ingredients were boiled in 60 of water for some 

 minutes, and when cold 20 of liq. animon. caust. were added. The 

 solution must be filtered before use. 



For staining, the procedure was as follows. Stain with Bohmer's 

 hsematoxylin or hsemalum, and differentiate with hydrochloric acid 

 alcohol. Then immerse the sections for 5 minutes in a mixture com- 

 posed of 2 parts of the carmin solution, i) of liq. ammon. caust., and 

 8 of methyl-alcohol. Differentiate in absolute alcohol 80, methyl- 

 alcohol 40, distilled water 100. Dehydrate in alcohol, and mount in 

 balsam. For staining nuclei, almost any preparation of carmin is more 

 or less useful, but the following mixture is effective : carmin 2, ammon. 

 chlorat. 4, hthium carbonicum 1, distilled water 100. Boil, and when cold 

 add liq. ammon. caust. 20. Keep in stoppered bottle, and add some 

 thymol to prevent mouldiness. 



RoTHiG, P. — Wechselbeziehung zwischen metachromatisclier Kern- und Protoplas- 

 mafarbnng der Ganglienzelle und dem Wassengehalt alkoholisclier Haematoxylin 

 Idsnngen. 



[Remarks on the diSerence of colour in nuclei after treatment with hsema- 

 toxylin solution variously diluted with water.] 



Zeitschr. iviss. Mikrosk., xxiii. (1906) pp. 316-18. 



* See this Journal, 1898, p. 686. t Op. cit., 1903, p. 768. 



J Centralbl. Bakt., Ref., xxxviii. (1906) p. 777. 

 § Zeitschr. wiss. Mikrosk., xxiii. (1906) pp. 319-22. 



