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this type of endosperm for a great number of Compositae. The 
similarity of my fig. 8 with f.i. that of fig. 17 of the endosperm 
in Sonchus arvensis in Dauierens (1919) paper is very striking. 
Summarizing the characteristics of embryosac development in 
Vittadinia triloba D.C. : 
No walls are initiated or formed during the meiotic divisions 
in the embryosac mother cell; 
The micropylar pair of megaspore nuclei forms the two 
nucleate stage of the definitive embryosac; 
The embryosac thus belongs to the Scilla type; 
The chalazal megaspores degenerate, with few exceptions where 
the nuclei divided once; 
The endosperm is probably cellular from the beginning. 
My thanks are due to the authorities of the Botanical Garden 
at Buitenzorg, especially to Dr. C. v. Faser, Chief of the Treub 
Laboratory, for kind permission to collect the material of 
Vittadinia, used in this investigation. 
