ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 001 



acquired a red colour, which they retained for a long time after removal 

 to pure water. Salamanders were injected in the peritoneal sac, and 

 frogs and toads in the dorsal lymph-sac. Mammals received an injec- 

 tion of O'l grm. to 100 ccm. of a 0*5 p.c. salt solution either in the 

 jugular vein or subcutaneously. It was found that not only cell- 

 granules, but also many other parts, were stained ; among these may be 

 mentioned the nuclei of the nervous system, the cells of hyaline cartilage, 

 fat-cells, and sarcolemma. The most striking reaction was the staining 

 of degenerated nerve-fibres. After death the red colour chauges to 

 yellow in many organs. 



Modification of the Iron Hematoxylin Staining Method. * — 

 A. Ch. Haemers immerses the whole object in a 5 p.c. solution of irun 

 alum for 2-8 days. After having been quickly washed in distilled 

 water, the piece is transferred to 1 p.c. hematoxylin solution for 4-8 

 days. During this period the fluid should be renewed two or three 

 times. After removal the preparation is washed in water and dehydrated 

 in.alcohol of increasing strength. When the spirit is no longer cloudy, 

 it may be imbedded in paraffin or celloidin. The sections may be con- 

 trast stained with Lichtgriin or with fuchsin. This method is successful 

 after fixing with chrom-osmic-acetic acid, with platiirum-osmic-acetic 

 acid, or with Midler's fluid. 



Intra vitam Staining of Micro-organisms, f — A. Cortes, who has re- 

 corded numerous observations showing the utility of intra vitam staining, 

 has now published drawings of numerous examples of micro-organisms 

 stained while alive with methylen-blue and other pigments. 



Staining Tubercle Bacilli and Spores by the Aid of Potassium 

 percarbonate and Hydrogen peroxide. £ — Dr. A. Midler has found 

 that for demonstrating tubercle bacilli in fuchsin-stained preparations, 

 the treatment with acid may be omitted, and replaced by potassium 

 percarbonate K 2 C 2 6 , or still better, by alkaline peroxide of hydro- 

 gen. The preparations do not suffer by protracted action of these 

 reagents, and the procedure is therefore specially suitable for material 

 which contains very few tubercle' bacilli. The same reagents can he 

 used with advantage in spore-staining. After staining the film with 

 carbol-fuchsin, the cover-glass is washed with dilute spirit (60-70 p.c), 

 or with water, and is then transferred to a freshly made 5-10 p.c. solution 

 of potassium percarbonate for at least a quarter of an hour, after which 

 it is washed with water and stained with methylen-blue. Peroxide of 

 hydrogen alkalinised immediately before use by means of soda or 

 potash solution acts more rapidly and effectively than the potassium 

 percarbonate. For spores, the method gives better results with anilin- 

 water-fuchsin than with phenol-fuchsin. 



Staining with Brazilin.§ — Prof. S. J. Hickson gives the following 

 method for staining with brazilin (C 1); H 14 5 ), which is extracted from the 

 wood of Ceesaljpinia echinata. 



The sections are placed in a solution of iron-alum (1 p.c. iron-alum 



* Zeitscbr. wiss. Mikr., xviii. (1901) pp. 33-4. 



t C.R. Assoc. Franchise Avance. des Sci., 1900, 9 pp., 3 pis., and 19 figs.. Cf. 

 this Journal, 1900, p. (525. J Ceutralbl. Uakt , l te Abt., xxix. (1901) pp. 791-4. 

 § Quart. Joura. Micr. Sci., xliv. (1901) pp. 469-71. 



