52 



THE JOURNAL OF PHARMACOLOGY. 



Distinctions Between the Official Hamamelis and that 



(Collected in the Spring.* 



By Grace E. Cooi^ey, Ph.D. 



The leaves of Hamamelis Virginica have matured their tissues before 

 the end of Maj^ and little ch'ange takes place in them before thej^ fall in 

 autumn. When treated with chloral hydrate or caustic potash, the leaves 

 give up oily matters, which collect in globules or masses on the slide. 

 This oil is very readily soluble in alcohol. It stains only faintly with 

 alkanet and takes only a faint yellow color with strong iodine. Osmic 

 acid stains it, but so it does the tannin present, and the reaction is ob- 

 scured. A strong odor of Witch Hazel is given off, when caustic potash 

 acts on the leaves. 



Fig. 1 



Fig. 2. 



Fig. 3. \\ 



Fig. 4. 



There is more tannin in the leaves in the fall than in the spring. Par- 

 ticles of Hamamelis powders sprinkled upon the surface of a^drop^of a 2 ^ 

 solution of chloride of iron blacken in two minutes, if the leaves were 

 collected in the fall ; and require three minutes to noticeably 'color if from 

 leaves of a spring collection. 



* Contribution to the work of " Research Committee C " of the U. S. Pharmacopoeia, 

 irom the Botanical Laboratory of Wellesley College. 



