CLASSIFICATION OF ANGIOSPERMS. 363 



d. APOCYNACE.E OR DOGBANE FAMILY. The plants 

 vary from perennial herbs to shrubs and trees, contain an acrid 

 latex, and have flowers with the stigmas and styles united and the 

 stamens distinct. They are mostly found in the Tropics. 



Apocyiiiim cannabiiniiii is a perennial herb with erect or 

 ascending branches. The leaves are oblong-lanceolate, opposite, 

 nearly sessile or with short petioles (Fig. 201, C, D). The flowers 

 are greenish-white, the lobes of the corolla being nearly er^ct and 

 the tube about as long as the calyx. The fruit is a slender, terete 

 follicle containing numerous seeds tipped at the micropylar end 

 with a tuft of hairs. The root is official (p. 467). 



The root of a closely related species, namely, spreading dog- 

 bane {Apocynuin androsamifoliiim) is sometimes substituted for 

 the official drug. The plant is distinguished by being more 

 spreading in its habit. The leaves are ovate (Fig. 201, A, B), 

 the flowers are pinkish, the lobes being revolute and the tube 

 several times as long as the calyx. 



Strophanthus Kornbe. The plant is a woody climber w'ith 

 elliptical-acuminate, hairy leaves. The flowers are fev/, character- 

 ized by long styles, and occur in axillary racemes. The fruit con- 

 sists of two long follicles containing numerous awned seeds (Fig. 

 185), which are official (p. 430). In the closely related plant S. 

 hispidus the flowers are numerous and occur in terminal cymes. 



Quebracho or Aspidosperma is the bark of Aspidosperma 

 Qnebracho-hlaiico, a tree growing in Argentine. It occurs in 

 nearly flat pieces which are i to 3 cm. thick ; the outer, surface 

 is yellowish-gray and deeply fissured, the inner bark being very 

 hard and tough. It is aromatic and bitter and contains six alka- 

 loids, all of which are present in the commercial aspidospermine. 

 They are aspidospermine, which is colored brown, then cherry- 

 red or purplish by sulphuric acid and potassium dichromate ; 

 aspidosamine, which is colored blue by sulphuric acid and potas- 

 sium dichromate ; aspidospermatine, which is colored deep red 

 by perchloric acid like the two preceding alkaloids, but not by 

 sulphuric acid and potassium dichromate ; quebrachine, wdiich is 

 colored yellow by perchloric acid ; and quebrachinamine, which 

 resembles quebrachine but has a much lower melting point. The 

 bark is used for tanning leather and yields a commercial extract. 



