352 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



obviate this, it should be recently prepared and carefully preserved 

 in tin cans with the addition of a few drops of chloroform. 



Ground flaxseed (flaxseed meal or crushed linseed) is not infre- 

 quently deficient in oil on account of its being admixed with " oil- 

 cake " or " cake-meal." The latter is the residue after expressing 

 about 20 to 30 per cent of the oil naturally occurring in the crushed 

 linseed, and the deficiency is sometimes made up by the addition 

 of mineral oils. Ground flaxseed sometimes contains fragments of 

 the cereals rye and wheat, which is partly due to the fact that these 

 cereals grow in with the flax, and partly because it is sometimes 

 shipped in meal or flour sacks. 



Constituents. Fixed oil 30 to 40 per cent; proteins about 25 

 per cent; mucilage in outer walls of the epidermal cells; ash 1 to 4 

 per cent. 



Allied Plant. In False Flax (Camelina sativa) of Europe the 

 sclerenchymatous fibers are replaced by broad, short stone cells, and 

 the epidermal cells on the addition of water eject a central column of 

 mucilage. 



ERYTHROXYLACE^:, OR COCA FAMILY 



A very small family represented by 2 genera, the more important 

 of which is Erythroxylon. They are mostly tropical shrubs with 

 entire leaves, 5-merous flowers and the fruit is a 1-seeded, reddish 

 drupe resembling that of dogwood. The anatomy of the plants of 

 this family closer resembles that of the Linacese. Of special interest 

 is the development of papillae on the dorsal surface of the leaves and 

 is characteristic of Erythroxylon Coca (Fig. 155). 



COCA. Coca Leaves. The leaves of Erythroxylon Coca, and 

 its varieties (Fam. Erythroxylacese), shrubs (Fig. 154) probably 

 indigenous to Bolivia and Peru, where they are extensively culti- 

 vated, as well as in Java and Ceylon. 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 pre- 

 ferred. 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. in length, 

 2 to 3 cm. in breadth (Fig. 154); summit acute, slightly mucronate; 

 base acute; margin entire, somewhat revolute; upper surface dark 

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



