LESSON x STAINING OF CELLOIDIN SECTIONS 45 



(3) Inoculate five milk tubes with the same varieties 

 of cholera vibrios, and keep them at 38 '5 C. 



Compare their mode of growth and curdling power 

 from day to day 



(4) Examine the hanging drop cultures of Vibrio cholerse 

 Asiatics previously made, and stain them with aqueous 

 gentian-violet. 



Actinomyces and Cladothrix 



(1) Inoculate an agar-agar tube with Cladothrix nivea 

 and another with Cladothrix asteroides. 



Keep them in the cool incubator at 22 C. 



(2) Stain actinomycotic tissue, embedded in celloidin, by 

 Gram's method. 



Some of the sections may be previously stained with 

 picrocarmine (vide p. 36). 



(a) Place the section on a slide and with a sharp scalpel 

 trim off the celloidin all round. 



(b) Dry the specimen with filter-paper. 



(c) Filter a little aniline gentian-violet on to the section, 

 and cover it over with a watch-glass, so as to protect it 

 from the dust. 



(d) After a quarter to half an hour remove the gentian- 

 violet with blotting-paper (sometimes five minutes is 

 sufficient). 



(e) Pour a little of Gram's iodine solution on the section 

 and allow it to act for one to two minutes. 



(/) Remove the iodine solution with I lotting-paper. 



