40 THE MICROSCOPE 



7.— Rosein or Aniline Violet. — Immerse in a spirituous 

 solution of rosein or aniline violet, then in an aqueous solution of 

 aniline blue or iodine green. 



9.— Borax Carmine and Indigo Carmine.— Two fluids are 

 required, red and blue. 



The former is made as follows : — carmine 7 J grains, borax 

 J drachm, distilled water i ounce. The blue contains indigo 

 carmine ^ drachm, borax ^ drachm, and distilled water 7 ounces. 

 After thorough trituration, the ingredients are mixed and left in a 

 vessel ; the supernatant fluid is then poured off. The sections, if 

 previously hardened in bichromate, picric, or chromic acid, 

 should be well washed ; they are then to be placed for a few 

 minutes in a mixture (equal parts) of the red and blue fluids, then 

 transferred, without washing, to a saturated solution of oxalic 

 acid, and allowed to remain in it rather less time than in the 

 staining fluid. When sufficiently bleached, the sections should be 

 washed in water until every trace of oxalic acid is removed. 

 Sections thus prepared may be mounted in Canada balsam or 

 gum dammar. Connective tissue substances are blue, while the 

 nuclei are red. The osseous lamellae of bone are blue, the cells 

 in the lacunae red, while the marrow is apple-green. 



10.— Methyl Green and Induline.— The one stains the nuclei 

 of the cells of the sub-cutaneous tissue, the nuclei of the vessels 

 of nerve sheaths rose colour, while the ceUs of the corium and 

 their nuclei are a violet red ; the other colours the cells of the 

 Malpighian layer a greenish blue. 



Methyl Green and Eosin are also very good. Eosin i part 

 and methyl green 60 parts are to be dissolved in a 30 % solution of 

 warm alcohol. The epithelial nuclei take a violet blue, the 

 nuclei of connective tissue a greenish blue, and the cell-body a red 

 colour. 



Note the singular differentiations : — Thus, while the striated 

 muscle is red, the nuclei are green. On the other hand, smooth 

 muscular tissue is green, the intercellular substance red. In the 

 salivary glands the cells of the excretory ducts are stained blue, 

 while the so-called secretory cells are red. Induline dissolves in 

 warm water and in dilute alcohol. Take a concentrated watery 



