NUCLEAR STAINS. 21 



For histological and pathological work, Hsematoxylin is 

 beyond doubt the best stain for general use. The nuclei are 

 clearly denned, the manipulation is easy, and good results 

 may be obtained with less experience than by any other 

 method. 



With Ehrlich's solution it is easy to stain the nuclei with- 

 out affecting the ground substance to any marked degree ; 

 whereas with Carmine and the Aniline dyes the two are 

 stained together, and it is less easy to remove effectually the 

 colour from the ground substance and leave the nuclei sharply 

 denned. 



When the tissues have been hardened in the Chromates, 

 the advantage of Haematoxylin over Carmine in rapidity of 

 staining is very marked. Carmine, on the other hand, pos- 

 sesses advantages in staining the nervous system, to which 

 Hsematoxylin is inapplicable, except by the somewhat tedious 

 process of Weigert or one of its modifications. 



H2EMATOXYLIN. 



This is essentially a nuclear stain, as it selects the nuclei 

 first ; but if the solution be too strong, or the action be con- 

 tinued too long, it will also stain the ground substance. It 

 is very extensively employed, and always in conjunction with 

 Alum, except in the special uses to which it is put in Weigert' s 

 method for the nervous system, in Heidenhain's method for 

 staining in mass, and Benda's copper method. 



Of the solutions, Ehrlich's and Delafield's are recommended 

 for sections, and Kleinenberg's for staining in mass. 



Sections are counter-stained with Benzopurpurine, Eosine, 

 Ery thro sine, or Rubin and Orange. 



Hsematoxylin has been objected to on the ground that the 

 solutions deteriorate by keeping, and that the stained sections 



