3°4 
The Ohio Naturalist. 
[Vol. V, No. 5 
NOTES ON THE MORPHOLOGY OF PHILOTRIA. 
Lvmina C. Riddle. 
The study of Philotria canadensis was begun by the writer in 
July, IhOd, with the expectation of making a careful investiga- 
tion of its morphological characters. 
On account of difficulty in obtaining a complete series the 
work was delayed and in the meantime a jireliminary report on 
the same subject was presented at the St. Louis meeting of the 
American Association for the Advancement of Science by R. B. 
Wylie and later the paper was printed in full, Bot. Gaz. 37; 1-22. 
So carefully has he worked out nearly every detail that there 
seems little to add to the subject except in the way of verifica- 
tion. Yet it is thought advisable to make a note of some of the 
most important jioints. 
Material for study was collected from Sandusky Bay, Lake 
Erie where the plant grows more or less abundantly but blooms 
rather uncertainlv. None of the material obtained gave satis- 
factory stages bevond fertilization. The staminate flowers were 
found on the opposite side of the Bay from the carpellate colony. 
The staminate flowers were uniformly of nine extrorse bi- 
sporangiate stamens, the three center ones being more or less 
united by the filaments and in some cases these extended above 
so as to form a resemblance to a stigma. Staminodia were found 
also in the carpellate flowers, but these showed no traces of 
sporangia. 
Measurements of flowers which gave the archesporial cell 
stage were about 4 mm. long. Opened flowers varied in length 
according to the distance of the stem at their origin from the sur- 
face of the water. The average length was about 100 mm. or 
4 inches. 
The single archesporial cell cuts off one parietal cell usually. 
The primary sporogenous cell is always much the larger and 
divides into four megaspores the lowest being the functional one. 
The u]>per one was often quite long and was usually the last to 
succumb to the rapidly enlarging embryo sac. The widening of 
the embrvo sac was great in only one plane and was not very 
marked when sections were cut at right angles to that plane. 
The pouch-like form of the antipodal region was very noticeable. 
Miss Burr found a similar pouch in Vallisneria, Ohio Nat. 4: 439- 
443. In everv case three pale vescicular nuclei could be found 
deep in the pouch. In some cases a large brightly stained nucleus 
was found just above the antipodals but careful examination 
showed that it was either the lower polar nucleus in a typical 
eight celled embrvo sac or else the evidence was that there had 
been a division of the definitive nucleus and one of the first 
