of the right stain in this way better than if a given time were ad- 

 hered to. 



In the use of stains requiring a subsequent differentiation, the 

 rule is to over^stain and watch the differentiation carefully with the 

 microscope, stopping it when sufficient. In this case it is the differ- 

 entiation and not the staining that should be carefully regulated. 



78. In this course are employed : (i) Chloral hematoxylin, 

 (2) Ehrlich's acid hematoxylin, (3) Delafield's hematoxylin, (4) 

 Weigert's hematoxylin, (5) Borax carmine, (6) Alum carmine 

 (Grenacher's), (7) Paracarmine, (8) Hydrochloric acid carmine, 

 (9) Picro-carmine, (10) Safranin, (n) Gentian violet, (12) Methyl- 

 green, (13) Ehrlich's triacid mixture, (14) Eosin, (15) Erythrosin, 

 (16) Picric alcohol, (17) Picro-fuchsin ; also (18) Heidenhain's 

 iron hematoxylin, and special stains given subsequently under 

 "Special Methods." 



79. The combinations most employed are (a) hematoxylin 

 and eosin (or erythrosin), and (^) hematoxylin and picrofuchsin, 

 the former a double and the latter a triple combination. 



The following scheme indicates the manner of their employment : 



