1914] PETRY—OPHIOGLOSSUM PENDULUM 175 
of phloem and endodermis. At a little distance, the endodermal 
sheaths come into contact, then fuse to form a single sheath; the 
phloem shows the same behavior. Xylem parenchyma then 
appears between the two protoxylem strands and the usual diarch 
condition of the branch stele is established. 
The bud 
The vegetative reproduction of the species is accomplished by 
buds upon the roots, as in O. vulgatum. As many as three buds 
were observed upon a single root; the second leaf of the oldest bud 
was just appearing, while the youngest bud was a mere swelling 
about 5 mm. from the root tip. Itis 
almost certain that the plants of a 
colony have all developed from a 
single plant by this method of vege- 
tative propagation; every rhizome 
examined in which the base is intact 3 
shows by its connection with a root > ‘Jb 
that it has developed from a bud; | 
fig. 5 represents such a case. 
Rostowzew (7) has described the 
development of the bud in O. oul- oe ae eee 
Saium. In the second segment of or Prise a, stem tip; /b, 
the apical cell of the root a new base of a decayed leaf; r, parent 
apical cell arises; this produces all root; Xr. 
stem tissues. The root apical cell is 
retarded for a time, but finally resumes growth. This results in 
the formation of a bud with its axis approximately at right angles 
to the parent root. 
__ The development of the bud has been examined in O. pendulum; 
t agrees in all important points with that of O. oulgatum. The 
retardation of the root growth is usually less; the bud axis often 
diverges less abruptly from that of the root. Two roots usually 
develop upon a bud before the first leaf is formed. The details of 
© vascular connection between the stem developed from a bud 
and the parent root will be described later. 
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