106 



other. Somewhat to the side of the developed bud a tendril 

 is always produced and t represents the bundle from this ten- 

 dril. It^ It^ are leaf-trace-bundles from the second node above , 

 and there thus remain only the four bundles {li) over. These, 

 investigated in their longitudinal course, prove to be formed by 

 the union of bundles from the higher internodes homologous 

 to those already described. The course of the bundles in the 

 stem will be clear from PL XIX Fig. 3. It is chiefly remarkable 

 from a monosymmetric character due to the peculiar morpho- 

 logy of the plant. 



It may seem at first sight as though the four bundles {v) , 

 formed l^y the union of bundles from lateral organs of higher 

 nodes, correspond pretty closely in position to the four large 

 bundles of anomalous phloem. This correspondence is however 

 not always very accurate, especially in the nodal regions. 

 There are also other circumstances which would indicate that 

 no close connection exists between the anomalous formations 

 and the bundles in question. In the first place there is no 

 contact between the primary vascular tissue and the secondary 

 formations in the pith, since the latter stand free in the me- 

 dullary tissue; and furthermore, as the investigation of youn- 

 ger stages in the growth of the stem immediately shows, the 

 anomalous structures in the pith have a later and quite inde- 

 pendent origin and mode of development. Thus if an inter- 

 node not more than 3 mm. thick is viewed in cross-section, 

 the pith will be found to be entirely normal and with no trace 

 of the remarkable formations found in older stems, although 

 the primary fibro-vascular bundles are well developed and have 

 already undergone considerable secondary thickening. The ano- 

 malous cambiums make their appearance about the time the 

 stem reaches a maximum diameter of 4 mm. and are devel- 

 oped directly by tangential divisions in the medullary paren- 

 chyma without being preceded by any primary formation of 

 fibro-vascular elements in the pith. This may be seen from 

 PI. XVIII Fig. 3 where a strip of the anomalous cambium at an 

 early stage of its development is represented , and the fact is 



