THE ANATOMY AND AFFINITY OF DEPARIA MOOREI, HOOK. 



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inwards through the cortex, gradually transforming the originally thin-walled storage 

 cells into hard, thick-walled tissue. In the oldest portions of the axis the pith is, in 

 like manner, partially or completely transformed. 



The vascular system is a perforated dictyostele, appearing in transverse sections 

 of a robust portion of the axis as a ring of usually small, irregular meristeles around 

 an ample pith, and surrounded by a broad cortex containing numerous leaf-trace 



bundles and roots (text-figs, i, viii). The general outline of those sections is 

 usually very irregular, for the leaf-bases vary in size, and, crowding one upon another 

 on the surface of the axis, merge gradually into the general cortical tissue. 



From each leaf-gap of the dictyostele there gradually pass out to a leaf-base a 

 group of four or five leaf- trace bundles. Should the leaf-trace consist of four bundles, 

 two are large and two small. The large bundles are to pass into the rachis towards 

 its upper or adaxial side, the smaller ones towards its lower or abaxial side. Should 

 the leaf-trace consist of five bundles, two are large and become adaxial in the rachis, 



