ZOOLOGY AND BOTANY, MI0R0800PY, ETC. 1039 



The author also uses test-tubes 25 cm. long and 3 cm. broad, ending 

 in a narrow tube 10-15 cm. long, which serves to connect with the air- 

 pump and gasometer. When the tubes are filled with a small quantity 

 of agar or gelatin they are inoculated, evacuated of air, and then filled 

 with the selected gas. This done, the tube is melted up and the tube 

 laid in the horizontal position. 



An original experiment of the author's in anaerobic cultivation was 

 to use Bacillus suhtilis as an agent to use up the oxygen. The gelatin 

 was boiled up in a tube with a narrow neck, then set by immersing in 

 ice-water, and at once inoculated. The inoculated gelatin was then 

 covered with a layer of agar inoculated with the B. suhtilis, whereupon 

 the tube was melted up. When the aerobic B. suhtilis began to develope 

 it absorbed the free oxygen present in the tube, and thereby created, for 

 the germs of the anaerobic microbes lying below, the proper condition for 

 their development. 



Cultivation of the " Typhus" Bacillus in coloured nutrient 

 media.* — Herr Birch-Hirschfeld has applied the method of staining 

 Bacteria in the living condition to the study of the morphology and 

 development of the typhoid Bacillus. The staining of the living Bacteria 

 was effected partly in drop-cultivations and partly in test-tubes. For 

 making the bouillon drop-cultures the author used the ordinary hollow- 

 ground slides. The cover-glass was fixed on a rim made out of 5 parts 

 vaselin and 1 part paraf&n. This rim was run on the slide with a turn- 

 table while the mixture was hot. This kind of rim allows the cover- 

 glass to be easily lifted up, and an incubation does not run into the 

 drop. Instead of the dyes usually adopted the author employed 

 phloxin-red, a pigment which does not cause, like fuchsin, methyl-violet, 

 &c., a granular precipitate to be deposited in the bouillon. Of a 

 sterilized watery 1 per cent, solution of phloxin-red 1 ccm. is added to 

 6 ccm. of sterilized slightly alkaline bouillon. Of this the drops are 

 made, and in it the typhoid Bacillus grows up coloured a bright red. 

 The spores, too, which remain unstained in cover-glass preparations, are 

 here (typhus and anthrax) brightly stained, and often more strongly 

 than the rest of the protoplasm. If the bouillon solution be less stained 

 than in the foregoing the spores only are stained. 



Benzo-purpurin in similar quantities is still more suitable for the 

 purpose than phloxin-red. This dye stains the spores brown. 



One of the positive results, according to the author, of this method 

 is to set at rest the disputed question of endogenous spores in typhoid 

 Bacillus. 



The author furthermore showed from the example of anthrax Bacillus 

 that Bacteria bred in this way are unaffected both in development and 

 virulence. 



New Method of cultivating Bacteria in Coloured Media for Dia- 

 gnostic Purposes.! — Dr. Noeggerath constructed a mixture of anilin dyes 

 to correspond as nearly as possible with the spectrum colours. Of these 

 dyes strong watery solutions were made, and then mixed in the following 

 proportions :— Me thylen-blue, 2 ccm. ; gentian-violet, 4 ccm. ; methyl- 

 green, 1 ccm. ; chrysoidin, 4 ccm. ; fuchsin, 3 ccm. This mixture was 

 then diluted with 200 ccm. water and added unfiltered to the gelatin in 

 the proportion of 7-10 drops to about 10 ccm. of the latter. The whole 



* Arch. f. Hygiene, vii. (1887} p. 341. f Fortschr. d. Med., vi. (1888) p 1 



4 A 2 



