308 R. H. Compton. 
pericycle and endodermis, and carrying in its concavity a small 
strand of sclerenchyma, which, as above described, passes some 
little distance up the petiole and then disappears. The internal 
cylinder of the stem does not contribute to the leaf-trace directly, 
the complications due to the presence of inrolled margins in the 
leaf-trace of M. fectinnta being absent in the species under 
consideration. 
After the departure of the leaf-trace the haplostele approaches 
the margin of the gap in the solenostele from which the leaf-trace 
first became detached. A fusion takes place, the xylems of the two 
steles becoming continuous. Latar on the other margin of the 
solenostele gap fuses with the axial strand, so that the internal 
ground-tissue is once more cut off from the exterior, remaining as a 
U-shaped strand in transverse section. The edges of the U 
, Fig. 43. T.S. of a portion of the central tissues of the rhizome in the 
region shewn in Fig. 5 D. tr., tracheids; protoxylem ; x.b., xylem 
parenchyma; //(., phloem; i.fh., internal sieve-tubes; />., pericycle- e 
endodermis, r J > •> 
