358 Morphologie, Teratologie, Befruchtung v Cytologie. 



Bless, M. C, A Contribution to the Life-history of Viola. 

 (Ann. Bot. XXVI. p. 155-163. pl. XVII— XIX. 1912.) 



The author has investigated the development of the female 

 gametophyte and the process of fertilisation in the chasmogamic 

 flowers of a number of species of Viola. In the paper a general 

 description of this part of the life-history is given, different species 

 being used to illustrate different stages. The author proposes to 

 complete the work in the future by an examination of the cleisto 

 gamic flowers. 



The present record shows that, in the chasmogamic flowers of 

 Viola, the development of the female gametophyte, and the fertili- 

 sation, are perfectly normal in all important features. Double ferti- 

 lisation was observed in Viola cucullata. 



Agnes Arber (Cambridge). 



Compton, R. H., Note on a case ofdoubling ofEmbryo- 

 sac, Pollen-tube and Embryo. (Ann. Bot. XXVI. p. 243—244. 



1912.) 



This note relates to a hybrid Lychnis (a member of the second 

 generation from the cross L. alba, Mill. X L. flos-cuculi, Linn.) 

 which was pollinated by L. flos-cuculli. The author observed , in an 

 ovary of this plant, an ovule containing a normal Single nucellus, 

 which, however, included two embryo-sacs. Each embr} T o-sac was 

 penetrated by a pollen-tube, and each contained a two-celled embryo. 

 The author points out that no similar case is recorded in the lite- 

 rature, but he draws attention to the fact that Gaertner grew two 

 exactly similar individuals from a Single seed of Dianthus barbatus 

 X D. sitperbus, another hybrid in a genus closely related to Lychnis. 



Agnes Arber (Cambridge). 



Pfeiffer, W. M., The morphology of Leitneria floridana. (Bot. 

 Gaz. LIII. p. 189-203. pls. 18—20. Mar. 1912.) 



In its development the ovule shows an unusually large amount 

 of parietal tissue, internal to which are formed four megaspores, 

 one of which develops into a normal embryo-sac. The endosperm 

 shows the stages of free cell formation and wall formation; this 

 later becomes a thin layer, surrounded by a few layers of perisperm 

 cells, and enclosing a large flat embryo whose differentiation occurs 

 rather late. It is still doubtful in which famity of Archichlamydeae 

 the plant should be placed. The possibility of derivation of Amen- 

 tiferae from gymnosperms is suggested. M. A. Chrysler. 



Stevens, N. E., The morpholoory of the seed of buckwheat. 

 (Bot. Gaz. LIII. p. 59—66. Jan. 1912.) 



Contrarjr to earlier Statements, Fagopyritm is found not to have 

 perisperm. In the development of the endosperm, walls make their 

 appearance only in the micropylar portion, though no wall divides 

 the embryo-sac into halves. In the outer region of the endosperm 

 a "cambium" makes its appearance, cutting off cells on its inner 

 side. The outer cell layer of the nucellus functions as a sort of 

 nutritive jacket. M. A. Chrysler. 



