1908-9. ] THE STELE OF OSMUNDA CINNAMOMEA. 515 
THE STELE OF OSMUNDA CINNAMOMEA. 
BY jc. HAULL BLA: PhD. 
THE SEEDLING. 
HITHERTO the seedlings of three members only of the Osmundacee 
have been described, namely Osmunda regalis by Leclerc du Sablon (8), 
Todea hymenophylloides by Seward and Ford (12), and Todea Frazert 
by Chandler (3). Leclerc du Sablon’s description is very brief; he states 
that the course of development of the stem in Osmunda regalts is essen- 
tially the same as in other ferns. The base of the stem is occupied by a 
protostele, farther up a pith makes its appearance and simultaneously 
the cylinder of xylem is broken by gaps above the points of departure 
of the leaf-traces. He notes the lack of internal phloem and internal 
endodermis, but points out that a similar condition prevails in Polpodiwm 
aureum. 
Seward and Ford state that their examination of the seedlings of 
Todea hymenophylloides proves that this species of Todea agrees in essen- 
tials with Osmunda regalis. The point of greatest interest in their account 
is the assertion that they could discover no trace of an endodermal layer 
in the medullary region of the seedling stele. 
Chandler (3) in the course of his rather extensive paper on fern seed- 
lings describes Todea Fraseri, the details of the development of which are 
like those of Todea hymenophylloides. 
Reference Was made by Faull (4) to some rather young plants of 
Osmunda cinnamomea, but their incompleteness, especially in regard to 
the youngest and the critical stages, forbade any detailed account. Quan- 
tities of seedlings in all stages, however, were found by the writer, in the 
neighbourhood of Stratford, Ontario, in the autumn of 1992, growing on 
hummocks in an open swampy tract of rich, but badly drained land, and 
the following description is based on these plants. 
With regard to the primary root and the transition region between 
root and stem, nothing new presents itself with one noteworthy exception, 
a so-far unrecorded feature for any member of the family. A fungus in 
abundance occupies the cortical cells of the primary and first formed 
