276 METHODS OF IDENTIFICATION AND STUDY 



3. Staining Reactions. 



1. Gram's Method. Positive or negative. 



2. Neisser's Method. If granules are noted, record 



1. Position. 



2. Number. 



3 . Ziehl-Neelsen's Method. Acid-fast or decolourised. 



4. Simple Aniline Dyes. (Noting those giving the 

 best results, with details of staining processes.) 



Methylene-blue 



Fuchsin 



, . . ! , \ and their modifications, 



Gentian violet 



Thionine blue 



BY BIOCHEMICAL METHODS. 



Test cultivations of the organism for the presence of 



Soluble enzymes proteolytic, diastatic, invertase. 



Organic acids (a) quantitatively i. e., estimate 

 the total acid production; (b) qualitatively for formic, 

 acetic, propionic, butyric, lactic. 



Ammonia. 



Neutral volatile substances ethyl alcohol, aldehyde, 

 acetone. 



Aromatic products indol, phenol. 



Soluble pigments. 



Test the power of reducing (a) colouring matters, 

 (b) nitrates to nitrites. 



Investigate the gas production H 2 S, CO 2 ,H 2 . Esti- 

 mate the ratio between the last two gases. 



Prepare all cultivations for these methods of ex- 

 amination under optimum conditions, previously deter- 

 mined for each of the organisms it is intended to investi- 

 gate, as to 



(a) Reaction of medium ; 



(b) Incubation temperature; 



(c) Atmospheric environment; 



