BRIEPER ARTICLES 
NOTES ON THE EMBRYOLOGY OF THE NYMPHAEACEAE 
(WITH PLATE VI) 
Within the- past few years the embryology of the Nymphaeaceae has | 
attracted considerable attention, beginning with Lyon’s studies oD ~ 
Nelumbo,* followed by my own paper on Castalia odorata and Nymphaeo — 
advena? and by Conarp’s3 monograph on the water lilies. The differences 
of opinion as to certain characters of the embryo, expressed by ConaRD | 
on the one side and Lyon and myself on the other, led me to believe that 
the embryological characters are subject to considerable variation, or that 
some serious error had been made. However, I determined to verify my _ 
work on Castalia odarata and Nymphaea advena, if possible, and YORK’ 
work on Nelumbo. Recently SEaTons has published a paper on Ny 
phaea advena, which also deserves consideration in this review of the subject : 
odorata, Nymphaea advena, and Nelumbo lutea, and therefore other species 
and other questions have been given very little or no consideration. 
EMBRYO SAC a 
The mature embryo sac is subject to considerable variation. Howevel, 
Tam now convinced that the formation of a cross-wall between the two 
daughter nuclei, which are formed by the first division of the endospem™ 
nucleus, is a constant character, although SEaTon failed to find it in NV. 
phaea advena. It is usually very delicate and is no doubt frequently 
‘ Lyon, H. L., Preliminary note on the embryogeny of Nelumbo. Science N.S 7 
132470. Ig00. 
———-, Observations on the embryogeny of Nelumbo. Minn. Bot. Stud. 2:6 
655. Igor. 
2 Cook, M. T., Development of the embryo sac and embryos of Castalia 040 
and Nymphaea advena, Bull. Torr. Bot. Club 29:2I1-220. 1902. 
3 Conarp, H. S., The water lilies: a monograph of the genus Nymphaea. 
negie Inst. Wash. Publ. 4. I9 
Cook, M. T., The satis of some Cuban Nymphaeaceae. Bor. GAZ 
42 3376-392. mele ; 
4 York, H. H., The embryo sac and embryo of Nelumbo. Ohio Nat. 4:1677 
1904. 5 
* SEATON, Sara, The development of the embryo-sac of Nymphaea advent. 
Torr. Bot. Club 35: 283-290. 1908. 
Botanical Gazette, vol. 48] 
