The embryo-sac of Pandanus coronatus 
Doucrias H. CAMPBELL 
The Pandanaceae are generally regarded as one of the lowest 
families of the monocotyledons. For this reason it seemed worth 
while to examine the embryo-sac to determine whether it showed 
any evidence of primitive characters in its structure. 
Material was collected in Java in 1906, and a preliminary exami- 
nation showed very marked departure from the ordinary angio- 
spermous type. An account of the results of this investigation 
has already been published.* 
The oldest stages secured from my Javanese material showed 
fourteen nuclei in the embryo-sac instead of the eight nuclei found 
in typical angiosperms. Of the fourteen nuclei, two were at the 
micropylar end of the sac, the others at the chalazal end. It 
was impossible to tell whether this stage represented the condition 
at the time of fertilization, and further efforts were made to obtain 
material which would settle this important question. 
Through the kindness of Dr. W. R. Shaw, of Manila, I have 
received a large amount of material, very carefully preserved, 
which has furnished the stages of development that were desired. 
Dr. Shaw writes that the species is probably P. coronatus Martelli 
—a name supposed to be synonymous with P. fectortus Soland. 
Preparations made from this material showed a number of in- 
stances in which the pollen-tube was entering the embryo-sac, and 
a comparison of these with the latest stages found in the material 
from Java showed that the latter were by no means mature. 
Pressure of other work has made it impossible at this time to 
present a detailed account'of the development of the later stages 
of the embryo-sac, but it is hoped later to prepare a full 
account of the development both of the embryo-sac and embryo. 
The present note is intended to give a description only of the 
structure of the embryo-sac at the time of fertilization. 
*Bull. Torrey Club 36: 205-220. pl. 16, 17. 1909. 
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