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AMERICAN JOURNAL OF BOTANY 
[Vol. 9 
ovule it occasionally happens that two or more hypodermal cells appear 
slightly enlarged so that it is difficult to determine from which one the 
archesporial cell is to be derived. Very soon, however, one cell outstrips 
the others and gives rise to the embryo sac. While investigating the 
cytology of the potato, the writer has sectioned some hundreds of ovaries 
in all stages of development, and the number of ovules examined must 
have run into the thousands. In only three instances was an ovule found 
containing more than one embryo sac. Photomicrographs of two of these 
ovules are shown in figure I. 
Fig. I. Photomicrographs of two ovules of Solamim tuberosum, each containing two 
embryo sacs. X 260. 
It is a matter of common observation that the potato seldom produces 
seed, and in the writer's work the germ cells have been found in all stages of 
degeneration. In the ovules in question degenerative changes were in 
progress in the embryo sacs, in consequence of which the nuclear structures 
of the embryo sacs are not well shown. It will be noted that in each case 
one embryo sac is better developed than the other. The vascular strand 
supplying the ovule, branches in the funiculus, sending a branch toward 
either embryo sac. It was observed that the larger branch is given off 
in the direction of the better developed embryo sac. 
Because of the evident rarity of the condition here described, the writer 
is inclined to regard it as a strictly abnormal occurrence. The affected 
ovules are believed to have been abnormal from their inception. It is 
doubtless to be explained as a case of proliferation or doubling, analogous 
CO the hypertrophied condition known as fasciation sometimes observed in 
stems and other organs. 
Department of Horticulture, 
Clemson Agricultural College 
