1900] ENDOSPERM AND EMBRYO OF PEPEROMIA 9 
different stage of development, of the several nuclei in the endo- 
sperm cells of Staphylea pinnata and Corydalis cava. In these 
forms, according to Strasburger (’80), when walls appear about 
the endosperm nuclei several of these are enclosed ina single 
cell and these later fuse to a single nucleus. The fusion of 
polar nuclei during instead of before fertilization is found also 
in Allium fistulosum (Strasburger ?79, p. 21), and this case may 
perhaps be considered as analogous to that of the endosperm- 
forming nuclei in Peperomia. 
That these peculiarities of Peperomia are to be considered 
primitive rather than higher specializations seems to me unwar- 
ranted by the evidence at present available, especially when we 
consider the fact, which I have ascertained, that such closely 
related genera as Piper, Heckeria, and Saururus have essentially 
typical angiosperm embryo- sacs. These latter forms develop a 
small amount of endosperm in a manner similar to that found in 
such distantly related and certainly not very primitive forms as 
the Nymphaeacee. 
Again, the lack of any grouping of the extra peripheral nuclei 
in the embryo-sac of Peperomia fails to give any encouragement 
from this source to those who look upon the antipodal group in 
the angiosperins as a second egg-apparatus (Lotsy, ’99, p. 106). 
So also the fusion of the eight nuclei to form the endosperm 
nucleus, if we regard it as at all homologous with that of the 
polar nuclei, seems to indicate that this is a purely vegetative or 
nutritive process, rather than anything like a sexual fusion as 
suggested by Mann (’92). Finally, the development of the cell 
walls in the endosperm directly after nuclear division each time, 
instead of by the method of free celle formation, as in the pro- 
thallus of the higher pteridophytes, is not favorable to the view 
that Peperomia is a transitional form between these forms and 
the typical angiosperms. 
I am inclined to believe that the peculiarities of the embryo- 
sac of Peperomia have been secondarily acquired, and are analo- 
gous to those found in other angiosperms of peculiar habit, e. g., 
many aquatic, parasitic, and saprophytic forms, 
