172 



Fig. 5 (magnified 4 y). Leaf-tip with some ten knobs in 

 différent stages of development; from a and a' a 

 young sprout lias corne to light. 



Fig. 6 (natural size). Photograph of the apical half of a 

 leaf, on whose tip tlie biggest sprout, I hâve ob- 

 served, can be seen. (The leaflets on the first node 

 hâve been dropped). 



Fig. 7 (natural size). Young spécimen of a sucker. Great 

 number of such suckers appeared in spring on the 

 curved upper branches and the stem of the two 

 plants from the cooler hothouse. Thèse suckers 

 drew the attention, because the leaflets on their 

 flrst node remain scale-shaped just as they do with 

 the adventitious sprouts. 



Fig. 8 (magnified 200 x ). Section of a normal leaf-tip ; 

 ep. epiderm; st. stoma; p. palissade parenchyma; 

 subp. subpalissade cell; ski. sclerenchyma fibres; 

 sch. spongy parenchyma; b.h. vascular bundle. 



Fig. 9 (magnified 200 x). Section of a small yellow 

 vesicle; in the centre of the drawing hypertrophical 

 spongy parenchyma cells; surrounding the latter 

 brown-walled cells (x); under the biggest hyper- 

 trophical cells some compressed cells that hâve died. 



Fig. 10 (magnified 200 y). Section of a big yellow vesicle ; 

 numerous cells of the spongy parenchyma and 

 subpalissade cells are hypertrophical; to the right 

 cells with partition walls; in the middle of the 

 upper part of the section also enlarged palissade 

 cells. The darker drawn walls in the spongy pa- 

 renchyma are suberized. 



Fig. 11 (magnified 200 y). Section of a yellow leaf-tip 

 that was not yet perceptibly thickened. Hyper- 

 trophy of the spongy parenchyma and of the 

 subpalissade cells. 



Fig. 12 (magnified 400 y). Drawing of a hand-cut prepa- 



