405 
In Austin’s herbarium there is an autograph specimen from, 
James, which is probably the one referred to in the BULLETIN it-), 
labelled O. odtusifolium, Drummond’s No. 157, on which Austin has: 
written: “equals O. drachytrichum, Sch., of course it is O. obtusifo- 
fium,” as undoubtedly it is, James having sent him only a part. 
of Drummond’s 157, and not the same as that he sent Schim- 
per. The specimen of O. odtusifolium collected by Austin in: 
Jordansville Swamp, New York, 1868, above referred to, has. 
_ both acute and obtuse leaves on the same plants. These helped 
him, also, to confuse the two species. 
_ Unequal Segmentation and Its Significance in the Primary Division 
of the Embryo of Ferns. 
By Geo. F. ATKINSON. 
In studying the embryos of several species of the Polypodiacex, 
sections were obtained of the primary division which suggested 
the possibility of some fundamental law governing unequal seg- 
mentation of the egg, in some species at least. In finishing a 
camera lucida sketch of an embryo of Preris serrulata 1 noted what 
at first was not observed, the two cells with their nuclei were of 
unequal size. Thinking some error might have arisen in connec- 
tion with the first sketch the preparation was examined again, 
when it was easy to note the smaller size of the nucleus in the 
smaller anterior segment. Measurements with the micrometer 
Showed that the diameter of the nucleus in the posterior segment 
Was one-fourth to one-fifth greater than that of the anterior seg- 
ment. 
If this state of things were reasonably constant it would show 
a definite relation existing between the primary segmentation and 
the different functions of the two segments. That is to say, the 
nucleus of the egg first divides into two unequal nuclei, an an- 
terior one smaller than a posterior one; that these unequal nuclei 
govern the size of the two primary segments of the embryo by 
which that part of the plant chiefly concerned in supplying nutri- 
Ment, the root segment, is differentiated from that part chiefly 
