284 KANSAS UNIVERSITY SCIENCE BULLETIN. 



outer wall of the epidermal cells have not yet begun to thicken. 

 Figure 4 shows part of a cross section of a mature leaf. The 

 epidermis has become cutinized and the walls of the bast fibers 

 have become thick and lignified. 



The Peduncle. 



The peduncle has remarkably thick, strong bundles of bast 

 fibers just outside the phloem (fig. 35, g, and fig. 36, k) . These 

 strands of bast persist long after the rest of the peduncle has 

 disintegrated. The fruit hanging suspended by these flexible 

 threads is tossed about by the wind. This seems to be a device 

 for scattering the seeds when the balls of fruits begin to fall to 

 pieces in the spring. 



The Buds. 



The buds (fig. 30) while forming are entirely inclosed in 

 the bases of the petioles. In winter condition they are pro- 

 tected by cone-shaped scales (fig. 34) . The outer scale is thick 

 and hard. The next (fig. 34, b) is covered by a mass of resin 

 through which project numerous hairs about 2 millimeters 

 long. The inner epidermis of this scale contains in some 

 places as many as 1200 crystals of calcium oxalate to the 

 square millimeter. On removing this scale one leaf is exposed, 

 but the remainder of the leaves and the inflorescence are 

 inclosed in still another conical scale densely covered with 

 straight hairs 2 millimeters long, consisting of a chain of 

 about four elongated cells. If the bud contains an inflo- 

 rescence, the inflorescence is terminal as shown in figure 31, 

 and there is a series of foliage leaves below it. Such a limb 

 continues its growth by a lateral bud in the axil of the last 

 leaf. The peduncle which terminates the main axis is pushed 

 to one side by the development of the axillary bud at its base, 

 which then has the appearance and later performs the func- 

 tion of a terminal bud. Usually a large, vigorous bud and one 

 or two smaller buds are inclosed together in the same outer 

 scales. The weaker buds usually do not develop. Some of 

 them begin to unfold, and then fall. The terminal bud may 

 contain one or two flower buds, one or two leaf buds, or both 

 leaf and flower buds. The terminal bud may produce either 

 pistillate or staminate flowers, and the same thing is true of 

 the lateral buds. 



Figures 37 to 42 show how the rings of vascular bundles of 

 three separate buds merge into the one ring of the stem 



