ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 521 



Differential Diagnosis of Bacillus typhosus and Bacillus coli by 

 means of Coloured Cultivation Media.* — E. Calandra used the follow- 

 ing media : 1. Broth and gelatin stained with litmus. 2. Media stained 

 • with picric acid and litmus. 3. Broth and gelatin with brilliant kresyl- 

 blue. 4. Broth with Congo red. 5. Broth with neutral red. 6. 

 Broth with Kuhne's alkali blue. The author claims that there are 

 obvious differences produced in the media by the action of these two 

 organisms : verbal description is inadequate to convey these differences, 

 and ocular demonstration is necessary. They presumably depend on 

 acidifying action of B. coli. 



Cultivating Bacillus tuberculosis.!— A. Frouin has devised a 

 medium which is said to be specially favourable to the growth of the 

 tubercle bacillus. It is composed of water 1000, sodium chloride 6, 

 chloride of potassium 0*3, disodium phosphate 0" 5, magnesium sulphate 

 0"3, calcium chloride 0*15, glycerin 40, glucosamin 2, sarcosin 2. The 

 solution is neutralised, sterilised, filtered, distributed into flasks and 

 sterilised anew. Though growth for the first fortnight after inoculation 

 is slow, in four weeks it is abundant, and by that time a thick film has 

 formed. 



Cultivation of the Leprosy Bacillus. i. — M. T. Clegg gives further 

 details as to the cultivation of the leprosy bacillus. § Inoculations were 

 made from the spleens and cutaneous nodules of ten lepers. In eight of 

 the ten instances an acid-fast bacillus was obtained in transplants of 

 aince.bal cultures, to which the leprous material had been added. By 

 heating such an amoeba-cholera-leprosy culture for h hour at 60° C. and 

 incubating, colonies of the leprosy bacillus were obtained, which grew 

 readily in pure culture when transplanted to the ordinary laboratory 

 media (e.g. agar, broth, eggs). Guinea-pigs inoculated subcutaneously 

 with the pure culture developed in some instances lesions at the site of 

 inoculation which bore a certain resemblance to the leprous lesions of 

 man, both macroscopically and microscopically. The acid-fast organisms 

 were found at the site of inoculation, and in some instances also in the 

 spleen. 



(2) Preparing- Objects. 



Fixation of Algae by means of Quinone. || — When fixing vorticelke 

 on fresh-water algae by means of quinone, A. Bonnet made observations 

 as to the effect of the reagent on the algai. He found that a 4 : 1000 

 solution gave excellent results. Sea-water may also be used, but the 

 solution turns brown more rapidly than in fresh-water. Once fixed, the 

 algae are more resistant to contraction and deformity when being de- 

 hydrated preparatory to mounting in glycerin-jelly, in glycerin, or in 

 ( lanada balsam. The chlorophyll stains greenish-brown ; spores and 

 eggs brown, the rest of the protoplasm yellow, and the cellulose mem- 

 branes are unaffected. 



* Centralbl. Bakt., !> Abt. Orig., liv. (1910) pp. 567-75. 



t C.R. Soc. Biol. Paris, lxviii. (1910) p. 915. 



% Philippine Journ. Sci., iv. (1909) pp. 403-14 (2 pis.). 



§ See this Journal, 1909, p. 061. 



||. C.R Soc. Biol. Paris, lxviii.. (1910) pp. 957-8. 



