DR THOMAS R. FRASER ON STROPHANTHUS HISPIDUS. 1001 



ledons and embryos, on the other hand, was opaque, pale yellowish-white, brittle, and 

 inodorous ; and it retained these characters without change for several months. The 

 differences in composition are stated below. 



Analysis No. 14. 



Alcoholic extract of testa, 4*58 grains, yielded — 



Impure strophanthin, 2 - 7 grains = 58'95 per cent, of extract, or 5*13 per cent, of testa. 



Mucilage, 0'875 grain = 19-104 „ „ 1-663 „ 



Resin, 0"94 grain =20-545 „ „ 1-663 „ „ 



Alcoholic extract of cotyledons and embryos, 4*865 grains, yielded — 



Impure strophanthin, 3765 grains = 77 - 4 per cent, of extract, or 5-65 of cotyledons and embryos. 



Mucilage, 0-48 grain = 9866 „ „ 0-719 



Resin, 0-44 grain = 9-044 „ „ 067 „ 



On comparing the above analyses, it is seen that the alcoholic extract of the testa 

 contains less active principle and much more mucilage and resin than the alcoholic 

 extract of the cotyledons and embryos. When derived from the testa, each of these 

 products is also much more coloured than when derived from the cotyledons and embryos. 

 The alcoholic extract of the seeds, therefore, obtains most of its colouring matter, muci- 

 lage and resin from the testa, and most of its strophanthin and oil from the cotyledons 

 and embryos. 



Reactions of the Alcoholic Extract. 



The action of a considerable number of reagents has been tested upon both the dry 

 extract and a watery solution of it. 



Dry Extract. 



1. Moistened with strong sulphuric acid, it first became pale yellow, then brown, and 

 in a few seconds emerald-green. In about a minute the green was almost completely 

 displaced by brownish-black, and in about an hour dark green became the predominating 

 colour, but it passed in another hour into greyish-green. 



When, after the addition of strong sulphuric acid, the extract was placed in a chamber 

 heated to 105° F., and the temperature was gradually raised to 120° F., the green colour- 

 soon became much intensified, and in about an hour and a half it passed into a dirty 

 green, and ultimately into a nondescript grey, through which numerous black particles 

 were diffused. 



2. With dilute sulphuric acid (10 or 2 per cent.) no material colour change was pro- 

 duced within several hours, provided the extract were originally only a slightly coloured 

 one. When the solution was then heated to 120° F., it gradually became light green, 

 dark green, bluish-green, deep blue, violet-blue, deep violet, and ultimately violet-black 

 and brownish-grey. 



The final coloured products of 1 and 2 are insoluble in water. 



