1908] CURRENT LITERATURE 155 
and the conclusion reached is that the fusion hypothesis is the most tenable; that 
is, the two lateral cotyledons of primitive angiosperms have become phylogeneti- 
cally fused in monocotyledons, and the result appears as a terminal member. 
The anatomical proofs of this position are fairly well known and seem cogent. 
The final question asked is as to the cause of fusion, and the answer is, the geophi- 
lous habit of the primitive monocotyledons. The author recognizes the fact that 
there are other distinctive features of monocotyledons which geophily cannot be 
called upon to explain, but these are “(departures from the primitive type.” 
To boil it all down: the angiosperms are monophyletic; the monocotyledons 
are derived from the primitive dicotyledonous stock; the terminal “cotyledon” is 
a historical fusion of two lateral cotyledons, which was induced by geophily; and 
the other characters of monocotyledons remain to be explained.—J. M. C. 
Polar conjugation in angiosperms.—Recently'? PoRscH attempted to explain 
the embryo sac and double fertilization in angiosperms. He holds that the two 
synergids are homologous with the neck canal cells of the gymnosperm arche- 
gonium (as to what gymnosperm has two neck canal cells, we are left in doubt); 
that the oospheres of gymnosperms and angiosperms are homologous; that the 
Upper polar nucleus is homologous with the ventral canal cell of the gymnosperm 
archegonium; and that the antipodal end of the angiosperm sac is the equivalent 
of the micropylar end. The triple fusion results from the essentially female 
character of the polars. 
It is with considerable surprise that we find an observer so acute as ScHAFF- 
NER" writing that the view of Porsc# in regard to these homologies has much in 
its favor, and that his interpretation of the triple fusion seems correct. That the 
or gymnosperms and angiosperms are homologous, no one denies; but the 
other homologies are so inaccurate that to note them at all seems useless. 4n 
following the reduction of the archegonium, one notes in the bryophytes a shorten- 
ing of the neck and a diminution in the number of neck canal cells. In the 
= Filicineae there are two neck canal cells separated by a wall; in the higher 
Filicineae there is one binucleate neck canal cell, the wall always failing to develop. 
In the Hydropteridineae even the nuclear division fails to take place and there is 
only one small, uninucleate neck canal cell; while in the gymnosperms there 1s 
no neck canal cell at all. In some gymnosperms there is a ventral canal cell, sep- 
Stated from the egg by a wall; but in more cases there is only a nuclear division 
without the formation of a wall, and in Torreya even the nuclear division is sup- 
5 In the Gnetales we note the disappearance of even the archegonium. 
‘iach lling such a series, it is difficult to understand how anyone could propose 
homologies as those suggested by PorscH.—CHARLES J. CHAMBERLAIN. 
und ohn Otto, Versuch einer phylogenetischen Erklarung des Embryosackes 
oppelten Befruchtung der Angiospermen. Jena: Gustav Fischer. 1907- 
8 sss : 
S “\ SCHAFENER, JOHN H., On the origin of polar conjugation in the angios : 
10 Naturalist 8: 255-258. 1908. 
