1920] EDWARDS— HEDYOSMUM 411 









Each flower is subtended by a hood-shaped bract, in the axil of 

 which it arises. This bract, in early development, completely 

 incloses the carpel and perianth (figs. 8, 12, 24). 



When first observed, the young female flower consists of a short 

 oblique column of tissue which is triangular in cross-section. On 

 the side directly opposite the midrib of the bract the flower is 

 distinctly lower than the sides next to the bract (figs. 8, 10). 



Perianth. 



m 



is the appearance of a ringlike upgrowth of the marginal portions of 

 each of the faces of the triangular flower rudiment. This upgrowth 

 is the young perianth. In the earliest stages seen this ring is 



midrib of the bract. 



lying 



rudiment 



seen in cross-section is convex all around (fig. 11). Somewhat 

 later, however, the outer tissue of the rudiment, that is, the tissue 

 of the perianth, becomes much thicker on the three angles of the 

 young flower, and a distinct depression is evident midway of # the 

 length of the flower on each side between the two angles (figs. 9, 

 10 Po). The depressed area bounded by the perianth is the wall 

 of the carpel (fig. 17). This growth of the perianth continues 

 from all directions, until in the ripe seed the wall of the carpel is 

 overgrown by the perianth except for a small pore in each of the 

 three flat sides (cf. figs. 9, 10, 25). 



The character of the growth of the perianth is very evident 

 from cross-sections (figs. 11 [upper and lower flower], 18) and from 

 longitudinal sections (figs. 12, 14, 22). Only along a narrow 

 strip, up and down each of the three corners of the ovary (figs, n 

 [X, upper flower], 12 F), and at a likewise narrow circular band 

 around the upper third of the ovary (fig. 22 F), are the tissues of 

 the carpel and perianth continuous with each other. 



A delicate vascular bundle is differentiated in the perianth at 

 each of its three corners (figs, n, 16). This vascular bundle 

 divides into two near the top of the perianth, and these branches 

 turn one to the right and one to the left, and later are found to be 

 joined to an offshoot of a bundle of the carpel that pushes out into 

 the perianth through the zone of attachment near the top of the 

 ovary- (fig. 22). The point of emergence of this carpellary bundle 



