ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 
455 
Staining- Method for Differentiating Leprosy, Smegma, and Human 
and Avian Tubercle Bacilli.* — Dr. E. J. Marzinowsky records some 
observations which tend to show that the bacilli of human and avian 
tuberculosis, of leprosy, and smegma, can be differentiated by a simple 
staining procedure. The stains used were ordinary carbol-fuchsin and 
Loeffler’s methylen-blue. Bac. tuberculosis Jiominis does not stain by 
this method. B. tuberculosis avium is easily stained, i.e. it retains the 
red after having been treated with the methylen-blue solution. Bac. leprae 
is easily stained, but is decolorised by longer action (10 minutes) of 
the methylen-blue. Bac. smegmee takes the red stain. Thus, while 
human tubercle bacilli do not stain at all, the other three do, and these 
are differentiated by the action of the methylen-blue. 
Modified Flemming Stain.j — Mr. H. F. Roberts states that basic 
fuchsin (1 per cent, aqueous solution) can be satisfactorily substituted 
for safranin in the Flemming triple stain, and frequently gives a more 
brilliant red. The manipulation is the same. Slides are best left in 
the fuchsin overnight, and excess extracted with 35 per cent, alcohol. 
The extraction is slow enough to be easily controlled. 
Modification of the TJnna-Tanzer Method for Staining Elastic 
Fibres.J — The modification suggested by Sig. F. Livini is a combination 
of Unna’s old and recent orcein methods, and consists of two solutions : 
(1) Orcein 1 part, hydrochloric acid 1 part, absolute alcohol 100 parts ; 
(2) 95 per cent, alcohol 20 parts, hydrochloric acidj,0*l part, distilled 
water 5 parts. Thirty drops of the first solution are mixed in a watch- 
glass with 5-10 ccm. of the second. In this mixture are placed sections 
of material fixed in sublimate or alcohol. The watch-glass must be 
covered over to prevent evaporation. The sections remain in the solu- 
tion some hours or overnight. They are then washed 3 or 4 times in 
90 per cent, alcohol, dehydrated, cleared up in origanum-oil, and mounted 
in balsam. The sections may be after-stained with haemalum, borax- 
carmine, &c. if necessary. 
Modification of Neisser’s Stain for Diphtheria Bacilli.§ — Mr. F. 
Tanner and Dr. A. C. Coles recommend the following modification of 
Neisser’s method. (1) The films' from a culture or membrane are 
spread on slides or cover-glasses, preferably the former. (2) Next fix 
in the ordinary way by heat or by immersion for a few minutes in equal 
parts of ether and absolute alcohol. (3) Stain in methylen-blue solu- 
tion (1 grm. dissolved in 20 ccm. of 96 per cent, alcohol, and mixed 
with 950 ccm. water and 50 ccm. glacial acetic acid) for 10-30 seconds. 
(4) After washing, immerse in Gram’s iodine solution for 10-30 seconds. 
(5) Wash in water and stain in vesuvin solution (vesuvin 2 grm. 
dissolved in 1000 ccm. of boiling distilled water) ; filter for 10-30 
seconds. (6) Dry, and mount in Canada balsam. 
Thus stained diphtheria bacilli appear as slender rods of a yellowish- 
brown colour, containing a granule at each end and sometimes also in 
the centre. 
* Centralbl. Bakt. u. Par., l te Abt., xxv. (1899) pp. 762-4. 
t Bot. Gazette, xxvii. (1899) p. 398. 
t Monitore Zool. Ital., vii. (1896) pp. 45-7. See Zeitschr. f. wiss. Mikr., xv. 
(1899) pp. 476-7. § Brit. Med. Journ., 1899, i. p. 1213. 
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