ON EGGS OF MARINE ANIMALS 79 



I use this freshly prepared in either tap or distilled water. In 

 my hands, this modification Is superior to the orthodox Heiden- 

 hain method. Mordant and destaining are unchanged. (Just, 



I933-) 



(b) Safranin. — Safranin gives beautiful preparations espe- 

 cially of chromosomes in stages of mitosis. However, it often 

 proves a very refractory stain. When successful its brilliancy 

 renders the study of mitotic stages a real pleasure. I have used 

 all of the various recipes given for safranin, but I have never 

 obtained with any one of them preparations as beautiful as those 

 furnished by the method which I myself have developed for this 

 dye. Usually one is advised to secure safranin of a certain serial 

 number, as for example, Safranin o of Griabler. This is then 

 used in distilled water saturated with aniline oil or saturated in 

 alcohol or made up of equal parts alcoholic and aqueous solu- 

 tions. With either of these methods the same safranin used does 

 not give constant results. In such cases of failure one is often 

 advised that now the aniline oil is at fault. The failures can be 

 overcome with perfectly constant results by using my method 

 which follows: 



I. Author^ s method for safranin {or gentian violet). — The cells, 

 not only eggs, but others from Protozoa to human tissue cells, 

 are fixed in modified Meves solution, as given above, or in 

 Altmann. After washing in water and running up to 80 per 

 cent, alcohol, the cells are brought into double distilled aniline 

 oil. The aniline oil is changed five times. It is then replaced 

 with xylene or toluene and infiltration with paraffin follows. 

 The paraffin sections are treated as outlined above and the slides 

 thus brought to 50 per cent, alcohol. From this they are 

 removed to the safranin stain made up as follows: Equal parts of 

 safranin saturated in 95 per cent, alcohol and of safranin satu- 

 rated in distilled water, without aniline oil. The farther treat- 

 ment and differentiation of the sections are with acid alcohol and 

 clove oil, as given for the orthodox method for safranin staining. 



For gentian violet proceed in the same way. Sections of 

 cells cleared in aniline oil, as given above, take Flemming's 

 triple stain very beautifully. 



Plasma Stains. — The most commonly employed stains for 

 the cell plasma are eosin and Orange G. These are both easy 



