VOLUME XXXVII NUMBER I 
BOTANICAL “GAZEITE 
JANUARY, (1904 
THE MORPHOLOGY OF ELODEA CANADENSIS. 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY, 
LIL 
ROBERT BB.“ WYLIE. 
(WITH PLATES I-IV) 
THE Helobiales occupy a place of special interest among 
monocotyledons. Beginning with members having the simplest 
flowers, the group includes an ascending series of forms and 
finds its climax in the Hydrocharitaceae which display consider- 
able floral complexity. This series has attracted much attention 
from plant morphologists and early investigation naturally cen- 
tered among the simpler members. It was with the hope of 
adding something to the data concerning one of the higher forms 
that this study was undertaken Elodea further invites attention 
on account of its being one of the most specialized of submersed 
aquatics. 
My thanks are due Professor John M. Coulter and Dr. Charles 
J. Chamberlain for kindly suggestions and valued assistance. 
FLORAL DEVELOPMENT. 
The flowers of Elodea canadensis are usually borne singly in 
the axils of leaves, and are scattered along the stem in a loose 
indeterminate inflorescence. They are so far apart, however, 
being separated by fifteen to twenty internodes, that one flower 
is well developed before the primordia of the next younger one 
are established. 
The flowers are functionally monosporangiate, though rudi- 
ments of the suppressed parts are often present. Three sterile 
- P I 
