IOO THE TEACHING BOTANIST 



ments of Botany possess small teaching collections, and 

 these are of such value that every teacher of an 

 elementary course should aim to gather at least a 

 small museum. 



Many parts of plants, such as hard fruits, woody 

 stems, etc., may best be preserved dry, as indeed may 

 the entire plants themselves, in herbaria, of which I 

 shall speak presently. But the softer parts can be 

 kept only in some preservative liquid, though none is 

 known which will keep color well. A solution of three 

 per cent formaline in water will preserve color as well 

 as any, but it keeps some colors much better than 

 others ; and in it the important green tissues become 

 of a translucent unnatural shade, which is hardly worth 

 the having. 1 In my own collections I use a mixture of 

 two per cent formaline in thirty per cent alcohol, which 

 preserves the softest tissues perfectly in every respect 

 except color. Formaline is used in such small quanti- 

 ties that it is really very cheap ; and colleges and 

 schools are entitled by law to purchase, though with 

 rather complicated legal formalities, alcohol free of 

 internal revenue tax, which makes it cost only about 

 40 cents per gallon in quantity. Bottles for speci- 

 mens may be any one of the many forms of preserve 

 jars; but after considerable experience with their effect 



1 If one wishes to try to preserve the green color by other methods, 

 he may consult to advantage an article by A. F. Woods, in the Botanical 

 Gazette, XXIV, p. 206. 



