CANNABIS SATIVA 2.33 



cotyledonary plane so derived converge at a slightly higher level, 

 forming the vascular bundles that supply the first epicotyledonary 

 leaves. As maturation of the tangentially oriented metaxylem 

 and the epicotyledonary bundles proceeds, the pericycle becomes 

 active, resulting in a slight increase in the diameter of the hypo- 

 cotyl from this point up to the cotyledonary node. At the same 

 time, there is a differentiation of a large number of resin or latex 

 ducts in the phloem of the epicotyledonary bundles. As the 

 metaxylem is differentiated in a more and more tangential position, 

 it finally assumes a position with relation to the protoxylem so 

 that the two arms of the metaxylem are extended at right angles 

 to the cotyledonary plane. This orientation occurs slightly below 

 or at the cotyledonary node, the protoxylem lying between two 

 groups of metaxylem and in a line with them. In this manner, the 

 double bundle of the mid vein of the cotyledon is formed. 



In most instances, the primary xylem is definitely endarch at 

 the base of the cotyledon, but the protoxylem is separated from 

 the metaxylem by parenchymatous tissue. This relationship 

 persists to a point just above the middle of the cotyledon, where 

 the protoxylem and two metaxylem groups converge to form a 

 single bundle. At the base of the cotyledon, the midvein branches, 

 giving off a lateral endarch bundle on each side, one being diverged 

 at a slightly higher level than the other; and these lateral strands 

 in turn are branched to form two principal veins. In each case, 

 the divergent branch which is directed toward the apex of the 

 cotyledon becomes a primary lateral vein. (Fig. iii.) The other 

 branch descends to meet a similar one of the opposite cotyledon, 

 and the two meet at a point somewhat lower than their point 

 of divergence. This results in the formation of a continuous 

 V-shaped strand which lies in the intercotyledonary plane of the 

 cotyledonary collar. (Fig. iii.) 



The Stem. — The fiber of commerce is derived from the stem; 

 and, in consequence, its structure has been studied extensively 

 by textile engineers. Dewey (11) has described the ideal plant 

 as one which attains a height of 10 to lifeet, is 34 to % of an inch 

 in diameter at the base, and develops internodes 10 inches or more in 

 length. The stem should be prominently fluted, with a com- 

 paratively large central pith cavity so that it forms a hollow 

 cylinder that is more easily broken by retting, since in this type, 

 the fiber is generally tougher. 



