ZOOLOGY AND BOTANY, MICROSCOPY, ETC 265 



the mixture having been well shaken is left for several days before it 

 is decanted. This blue is termed lion-el's blue. 



Films of bird's blood infected with Laverania are fixed in absolute 

 alcohol for one hour, and then immersed in the following freshly pre- 

 pared staining solution : — Borrel's blue, 1 ccm. in a 1 per mil. aqueous 

 solution ; soluble eosin, 5 ccm. ; distilled water, 4 ccm. The blue and 

 eosiu solutions are filtered at the time of mixture and not afterwards. 



After 12—24 hours, the cover-glasses are washed in distilled water, 

 and then immersed for one or two minutes in a 1 per cent, aqueous 

 solution of tannin. The slip is then washed, dried, and mounted in 

 balsam. 



The uuclei of the Hasmatozoa are stained violet, the rest of the 

 protoplasm is uncoloured or faintly blue ; the red corpuscles are pink 

 and their nuclei violet. 



(5) Mounting-, including- Slides, Preservative Fluids, &c. 



New and more Permanent Method of Mounting Amyloid Sections 

 Stained with Iodine. * — Dr. A. B. Greeu recommends the following 

 procedure for mounting amyloid sections. Three solutions are required : 

 — (1) Weigert's iodine ; (2) liquid paraffin (30 ccm.) and iodine crystals 

 (1 grm.) ; (3) xylol (30 ccm.), iodine crystals (1 grin). First place 

 on a cover-slip white vaselin to be ready for mounting. Float the 

 section on to a slide, and remove as much water as possible. Drop 

 on some of solution (1) until the section is sufficiently stained. Drain 

 off* excess, and pour over some of solution (2). Drain away excess, and 

 pour on solution (3). Drain away excess, blot quickly, and put on 

 vaselined cover-slip at once. 



(6) Miscellaneous. 



Methods for Distinguishing between Bacillus Tuberculosis and 

 Bacillus Smegmae.f — Mr. W. C. C. Pakes points out that Bacillus 

 smegmae may be easily mistaken for Bacillus tuberculosis, and that it has 

 been found in sputum, wine, and milk. It djffers from the tubercle 

 bacillus in not being pathogenic to guinea-pigs, in its cultural reactions, 

 and its inability to resist the decolorising action of absolute alcohol after 

 having been stained with warm phenol-fnchsin. The following modified 

 Ziehl-Neelson method is advised : — The him, which should not bo too 

 thin, is dried in the air, and then passed thrice through the flame. The 

 preparation is stained with hot phenol fnchsin (60°) fur five minutes, and 

 then washed with water. Every visible trace of stain is removed in abso- 

 lute alcohol, and, after having been washed in water, the preparation is 

 immersed in 25 per cent. H 2 S0 4 for five or six seconds, and then washed in 

 water again. Having been contrast-stained for about three seconds in 

 phenol -methylen-blue, the preparation is washed, dried, and mounted. 



If there be any doubt, IlanseH's method may now be adopted. The film 

 is prepared and stained as before, but after washing in water, it is dried 

 and then immersed in acid-alcohol (absolute alcohol 97 per cent., HC1 3 

 per cent.) for ten minutes, after which it is washed in water. The prepa- 

 ration is contrast-stained for several seconds in equal parts of a saturated 

 alcoholic solution of methylen and water, washed, dried, and mounted. 



* Lancet, 1899, i. p. 581. f Brit. Med. Jonrn., 1900, i. p. 186. 



April 18th, 1900 T 



