Trichomanes javanicum , Bl. 1039 
endodermis. This species then resembles the T. spicatum type described by 
Boodle. 1 Text-fig. % is a diagram of a transverse section of the stem. The 
central stele, X, is giving off a meristele, a , which will later divide to form 
a branch and a leaf-trace; b is such a meristele which has travelled some 
distance in the cortex. A leaf-trace, c, has come off from the axillary branch, 
x, and lies on the same radius with it. The root d is just going off from x, 
the stem stele. 
In structure the meristele closely resembles that of the stem as it is 
given off. It consists of a solid mass of xylem and parenchyma surrounded 
by phloem, pericycle, and endodermis. It differs from the stem in having 
central protoxylem elements (PI. LXXX, Fig. i). This character is kept by 
the meristele as it passes through the cortex until it divides into branch and 
leaf-trace. This division takes place in some cases just before the meristele 
curves into the petiole, and in other cases the division is delayed until it has 
reached the petiole base or travelled a short distance up the petiole. The 
resulting strands lie on the same radius ; the inner smaller strand is that of 
the axillary branch and the outer strand is the leaf-trace. In T. radicans , 
where the axillary branch develops normally, the inner strand is larger than 
the leaf-trace. Its diminution in size in T. javanicum is due to the fact that 
it eventually perishes. 
1 loc. cit., p. 477. 
3 Y 3 
