QUEBRACHO 647 



principle appears to be more powerful than strophanthin, but is 

 less satisfactory as a heart tonic. 



Strophanthus Hispidus. The seeds of this plant were at one time 

 considered inferior to those of S. Kombe. This has been shown to be 

 erroneous and they are now quite extensively employed- They 

 resemble the seeds of S. Kombe but are of a light or dark brown color, 

 nearly smooth and very sparingly hairy. The bases of the hairs are 

 more strongly lignified. The endosperm layer is not colored so dis- 

 tinctly green with sulphuric acid. 



Allied Plants. The seeds of other species of Strophanthus, grow- 

 ing in the same regions with S. Kombe, sometimes occur in commerce. 

 Of these the following may be mentioned. The seeds of Strophan- 

 thus gratus are spindle-shaped, somewhat flattened, of a light yellow 

 or orange-brown color, nearly free from hairs and have a peculiar 

 bitter taste. The cells of the endosperm are colored reddish, becom- 

 ing violet, with 90 per cent sulphuric acid. The seeds of S. sarmen- 

 tosus, a small tree growing in Africa, from Senegal to Kongo Free 

 State, are shorter, thicker and more sparingly hairy than those of S. 

 Kombe. The seeds of Kickxia africana (Fam. Apocynacese), a tree 

 growing in western tropical Africa, are spindle-shaped, not flattened, 

 slightly twisted, not hairy and of a reddish-brown color. The cotyle- 

 dons are somewhat folded and not parallel as in Strophanthus Kombe. 

 With sulphuric acid the seeds are colored brown, changing to red. 



Adulterants. The seeds of Strophanthus sarmentosus contain 

 calcium oxalate and give a red color on treatment with sulphuric acid. 

 (U. S. Dept. Agric.) 



Literature. Rowe, A. Ph. A., 1916, 5, p. 1183. 



Aspidosperma. QUEBRACHO, CORTEX QUEBRACHO, QUEBRACHO 

 BLANCO OR QUEBRACHO BARK. The dried bark of Aspidosperma 

 Quebracho bianco (Fam. Apocynacese), a large tree indigenous to the 

 western provinces of the Argentine Republic, Chile, Bolivia and 

 southern Brazil. The name Quebracho is often applied to other 

 trees, the bark of which is very hard, alluding to the fact that in 

 felling the trees the sharp-edged tools applied to them are consider- 

 ably dulled and nicked, by the sclerenchymatous tissues of the bark. 

 The commercial supplies are obtained from the vicinity of Catamarca 

 and Santiago, in northwestern Argentine Republic. 



Description. In irregular chips or in longitudinal pieces attain- 

 ing a length of 20 cm. and a width of 6 cm., bark from 1 to 3.5 cm. in 

 thickness; periderm from 3 to 20 mm. in thickness, brownish-gray or 

 reddish-brown and deeply furrowed, frequently reticulate with longi- 

 tudinal and transverse fissures, the crevices being occasionally lined 



