134 



REGENERATION 



In such experiments as represented in Fig. 108, one cannot 

 count with certainty on the growth of the axillary bud. This is, 

 however, possible if the petiole of the leaf, where it joins the stem, 

 is reduced in size. It does not matter whether the lateral parts 

 of the petiole at the node are cut off as in Fig. 109, or whether a 

 piece is cut from the center of the petiole, where it joins the node 



Fig. 109. Fig. 110. 



Fig. 109. — An axillary shoot is formed when the petiole of the leaf at juncture 

 with stem is reduced laterally. Nov. 23 to Dec. 15, 192.3. 



Fig. 110. — An axillary shoot is formed when a hole is made through the petiole 

 in the center where it joins the stem. Nov. 25 to Dec. 15, 1923. 



of the stem, as in Fig. 110. In either case, a shoot will grow out 

 from the axillary bud of the leaf — provided the piece of half stem 

 is small as in Figs. 109 and 110. 



Is it lack of oxygen which prevents the axillary bud of a leaf 

 from growing into a stem or is there some other cause? The 

 writer is not in a position to answer this question at present. 



