i6o Rhizome of Matonla pectinata. 
triangular in longitudinal section (fig. 8). As I had only one apex 
*t my disposal, and this had to be cut longitudinally, it is impossible 
to say whether this cell is three-sided or four-sided in surface view, 
but it seems most probable, as Mr. Seward suggests, that it is 
three-sided. On each side of the apical cell are narrow cells, cut 
off parallel to the inclined walls, and these have divided again by 
tangential walls to form the meristem from which the various 
tissues of the mature rhizome are formed. 
Owens College, Manchester, 
May 23rd, 1902. 
Explanation of Plate III. 
Rhizome of Matonia pectinata. 
Fig. 1. Transverse sections of the steles, about half-an-inch in front of a leaf 
insertion, showing the innermost stele open on the dorsal side, the 
middle stele flattened dorsally and bent slightly towards the gap in the 
innermost stele. The dots mark the protoxylem groups. 
f=Innermost stele. 
;//=Middle stele. 
o=Outermost stele. 
Fig. 2. Transverse section slightly nearer the leaf insertion than Fig. 1, showing 
the innermost stele connected dorsally with the middle stele. 
Fig. 3. Transverse section still nearer the leaf insertion. The innermost stele 
has separated from the middle stele and a gap is left in the latter. The 
outermost stele is flattened dorsally. 
F'ig 4. Transverse section behind that of Fig. 3. The innermost stele is annular, 
the two free ends of the middle stele have bent outwards and the 
outermost stele has bent down between them. 
Fig. 5. Transverse section close to the leaf insertion, showing the innermost 
stele, still annular but narrower on the dorsal side. The middle and 
outermost steles have joined to form a double horse-shoe with a bar 
across. 
Fig. 6. Transverse section at the leaf insertion. The innermost stele is 
unaltered, the middle stele is separated from the outermost and is now 
annular. The outermost stele has a gap, and the incurved ends have 
elongated to supply the young leaf. 
F'ig. 7. Longitudinal section through apical region showing apical cells of 
rhizome and leaf. 
s£=Apical cell of rhizome. t=Innermost stele. 
/=Apical cell of leaf. w=Middle stele. 
;//>=Upper surface of rhizome. o=Outermost stele. 
Fig. 8. 
Portion of Fig. 7, more highly magnified. 
