6o4 BOTANY AND PHARMACOGNOSY. 



at an angle of about 60 and uniting with each other near the 

 margin ; under surface yellowish-green ; petiole about i mm. 

 long ; texture coriaceous, brittle ; odor slight ; taste astringent, 

 bitter. 



Constituents. A neutral, tasteless principle chimaphilin, 

 occurring in golden-yellow needles ; two glucosides arbutin and 

 ericolin (see Uva Ursi) ; several other crystalline principles; a 

 volatile oil ; tannin 4 to 5 per cent. ; calcium oxalate ; ash about 

 5 per cent. 



COCA. COCA LEAVES. The leaves of Erythroxylon 

 Coca, and its varieties (Fam. Erythroxylaceas), shrubs (Fig. 

 260) probably indigenous to Bolivia and Peru, where they are 

 extensively cultivated, as well as in Java and Ceylon (p. 303). 

 The leaves when fully grown are picked and quickly dried in the 

 sun; Two or three harvests are obtained a year. There are two 

 principal commercial varieties Bolivian (Huanco) and Peruvian 

 (Truxillo), the former being preferred. On keeping the leaves 

 the alkaloid cocaine is dissipated and they lose their stimulating 

 properties, particularly if they are not thoroughly dried. 



Bolivian Coca. Oval, obovate or elliptical, 3 to 7 cm. long, 

 2 to 3 cm. broad (Fig. 260) ; apex acute, slightly mucronate; base 

 acute ; margin entire, somewhat revolute ; upper surface dark 

 green, glabrous, midrib with a distinct ridge ; under surface yel- 

 lowish-green, distinctly undulate, with numerous minute papillae, 

 frequently with a parallel line about 4 mm. from the midrib on 

 either side and extending from the base to the apex ; petiole dark 

 brown, i to 6 mm. long; texture somewhat coriaceous; odor dis- 

 tinct ; with a bitter taste, and producing a sensation of numbness. 



Peruvian Coca. Leaves usually more broken, 3 to 5.5 cm. 

 long. 1.5 to 2 cm. broad; upper surface light green, ridge on the 

 midrib faint or wanting; under surface light yellowish-green, 

 the curved line on either side of the midrib visually wanting ; more 

 or less fragile ; sensation of numbness on tasting the drug not so 

 pronounced. 



The flowers of a species of Inga (Fam. Leguminosoe) are 

 frequently present. The pedicel is about 2 mm. long ; the calyx 

 yellowish-brown, about i cm. long, five-toothed, pubescent; 

 corolla cylindrical, or somewhat funnel-shaped, 5-toothed, about 



