CHAPTER III 
STAINS AND STAINING 
Since the third edition of this book appeared in 1915 no new 
stains of the first rank have come into favor, but much greater 
precision has been attained in the use of some which were already 
popular. For cytological work Haidenhain’s iron-haematoxylin 
holds a firm place at the head of the list, with Flemming’s triple 
stain an easy second. For anatomical work, safranin still holds 
first place for the lignified elements of the vascular system, but the 
claim of Delafield’s haematoxylin to first place for cellulose tissues 
is no longer undisputed, for anilin blue is giving excellent results and 
light green seems to give more accurate views of the phloem than we 
were securing with any of the other stains. The fact that excellent 
preparations can be made, almost without trial, by using combina¬ 
tions already perfected doubtless deters investigators from experi¬ 
menting with other stains. There is still abundant room for experi¬ 
menting with various stains, and especially in the use of mordants and 
in the effect of the same stain or combination after various fixing 
agents. It is to be regretted that botanists who need microtechnic 
have so little knowledge of chemistry, and that chemists have no 
interest in developing methods of staining. During the past few 
years, American stains have been developed until many equal and 
some even surpass the famous Griibler products; and, besides, the 
American stains are becoming standardized. 
Stains may be classified in various ways: e.g., there are three 
great groups of stains—the carmines, the haematoxylins, and the 
anilins. Stains may be classified as basic and acid, or they may be 
regarded as general and specific. A general stain affects all the 
elements, while a specific stain affects only certain elements, or 
stains some elements more deeply than others. Stains which 
show a vigorous affinity for the nucleus have been called “nuclear 
stains,” and those which affect the cytoplasm more than the nucleus 
have been termed “plasma stains.” Of course, such stains are 
specific. 
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