ON EGGS OF MARINE ANIMALS 8i 



eggs from 80 per cent, alcohol in aniline oil. Staining with the 

 Fuchsin S and the counter-staining are carried out as given 

 originally by Altmann or by Meves except that aniline oil is 

 omitted from the water in which the Fuchsin S is dissolved, if 

 the object has been cleared in aniline oil. 



Heidenhain's iron haematoxylin is in my experience as good 

 as, if not superior to, these special techniques for mitochondria 

 or for Golgi apparatus, if it is used after the modified Meves or 

 the Meves without glacial acetic acid. It is also successful after 

 Altmann 's fixation. In all these cases the cells may also be 

 cleared in aniline oil from 80 per cent, alcohol. It is sometimes 

 best, however, to replace the aniline oil not with xylene or 

 toluene but with chloroform. 



Stains for Spermatozoa 



Depending upon the fixative employed Heidenhain's iron 

 haematoxylin will bring out perfectly all of the structures in 

 motile spermatozoa. In some cases, however, it is advantageous 

 to employ stains in combination, as Flemming's triple stain. 

 After modified Meves, Altmann or Regaud, iron haematoxylin 

 brings out perforatorium, head, middle-piece and tail of the 

 spermatozoon very sharply. I have kept spermatozoa of marine 

 animals in Regaud for more than 20 years, in a solid cake. By 

 dissolving a bit of this dry material in water on a slide and 

 staining this, I have obtained a preparation in no wise inferior 

 to that of the freshly fixed and stained spermatozoa. The 

 great resistance of killed spermatozoa to change is well-known; 

 spermatozoa burnt to a char maintain their shape. 



Literature 



Just, E. E. 1933. A cytological study of effects of ultra-violet light 

 on the egg of Nereis limbata. Zeitschr. Zellf. mikr, Anat., Bd. 17. 



