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no equivalent on the opposite side of the stem. To one side 

 of the bud destined to develope into a branch, and removed 

 from it by 45° — 60' of the stem-periphery, arises the tendril, 

 the extra-axillary position of which at once attracts the atten- 

 tion, and invites investigation. On examining successive nodes, 

 due care being taken to eliminate the effects of tv\^i sting in the 

 long internodes , it will be seen that the branches do not occur 

 in the axil of either leaf at random but are confined to two 

 of the four orthostichies. Thus if the orthostichies be numbered 

 around the stem 1, 2, 3 and 4, the developing branches will 

 be found to occur first from the axil of leaf 1, then of leaf 2, 

 then again of leaf 1, 2, 1 and so forth; while on orthostichies 

 3 and 4 all the buds are abortive. The occurrence of the ten- 

 drils may be best understood by a reference to PI. XIX Fig. 3 

 where it will be seen that they arise first to the right of the 

 developed bud b r then to the left of b r' then again to the right 

 of b r" and so on ; in such a way that they stand in two lines , 

 which are nearly, but not exactly, on opposite sides of the stem. 

 If this be a monopodium the questions at once arise, why 

 are there constantly three buds in the axil of one leaf and 

 but two in that of the other, why are the developing branches 

 confined to two adjacent orthostichies, and what is the nature 

 of the tendrils. The difficulty of these questions points to the 

 fact that the stem of lodes may have a sympodial structure, 

 and leads to the consideration of the possible morphological 

 relation of the organs if the latter supposition be correct. As 

 the tendril does not stand in the axil of a leaf it may for the 

 moment be assumed that it represents the morphological end 

 of the stem. It is then necessary to account for the next younger 

 inter-node, which, in case our supposition concerning the ten- 

 dril is correct, must have arisen as an axillary bud. And in 

 fact, as we have just seen, no bud is to be found in the axil 

 of one leaf which corresponds to the developing branch in the 

 other. We have thus reason to suppose that the apparent axis 

 represents the bud which is missing. It may be objected, that 

 the bud a I) PI. XIX Fig. 1 may be the morphological equivalent 



