SECTION THREE 



Technique: 



1. Stain with Gram's iodine solution for a few minutes. 



2. Pour off excess stain ; rinse in distilled water. 



3. Mount in the glycerine solution; cover with a coverslip and 

 examine under the microscope. 



Results: 



Starch, navy blue. Proteins, brown. Cytoplasm, light brown. 

 Nuclei, dark brown. Chloroplasts, brown or blue. Cellulose walls, 

 faint yellow. Lignified walls, deep yellow. 



HAEMATOXYLIN (Heidenhain) - ANILINE BLUE 



For the difTerential staining of nuclei, cytoplasm and cell 

 walls of angiosperm shoot apices 



This technique which is due to Dr. J. G. Vaughan, Department of 

 Biology, Chelsea Polytechnic, London, S.W.3, has been used with success 

 on Anagallis and certain members of the Cruciferae. No mixing of the 

 dyes has been observed in the apical meristem region, as occurs with 

 other stain combinations, and the picture is clear and well defined, 

 thereby facilitating study and photographing. 



Solutions required: 



A. Haematoxylin (Heidenhain), No. i. 



B. Haematoxylin (Heidenhain) No. 2. 



C. Iron alum 2% aqueous. 



D. Aniline blue alcohol, soluble (Michrome 

 brand) . . . . . . . . i gm. 



Methyl cellosolve . . . . . . 100 ml. 



Dissolve by heating on a hot plate or a 

 waterbath, taking care that the cellosolve 

 does not catch fire. Allow to cool; then 

 filter. 



E. Methyl salicylate 25 ml. 



Xylol 



Absolute alcohol 



F. Methyl salicylate 

 Xylol 

 Absolute alcohol 



33 nal- 

 42 ml. 



40 ml. 

 20 ml. 

 20 ml. 



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