1902] CURRENT LITERATURE 7^ 



of bleeding which have been observed are pathological phenomena, depend- 

 ent either upon the stimulus of the wound by which the manometer was 

 brought into the tissue, or upon the development of abnormal tissue (such as 

 callus) covering the wound surface. The pressure arises, then, at or near the 

 wound surface and not far back in the plant body. Many experiments were 

 performed upon Juglans regia, Betula alba, etc., and all seem to support this 

 idea. The work of Figdor, C. Kraus, Pitra, and Wieler is discussed, and 



evidence drawn therefrom in support of the new interpretation,— B. E. Liv- 

 ingston. 



M, T. CooK^^ has published the results of a morphological study of Cas- 

 talia {Nyrnphaed) odorata and Nymiphaea i^Nuphar) advena. The develop- 

 ment of the megaspore and of the structures of the embryo sac is reported as 

 presenting no new features. The first division of the definitive nucleus is 

 followed by a wall across the embryo sac. In the upper chamber the endo- 

 sperm develops, while the lower extends as an haustorial tube to the chalazal 

 extremity of the ovule. The embryo is at first a spherical multicellular 

 mass, as described by Lyon and Conard, and later forms what the author, in 

 agreement with Lyon, regards as a single cotyledon. Following Lyon, he 

 would regard this as justifying the transfer of the Nymphaeaceae to the 

 monocotyledons.— J. M. C. 



Miss Sibille O. Ford ^' has been studying the anatomy and develop- 

 ment of Ceratopteris thalictroides. She finds that the plant is annual, and is 

 often reproduced by adventitious buds originating in the angles between the 

 lobes of the leaves. The bundles are generally bicollateral, and the cauline 

 bundle system consists of an outer series of large strands and of smaller 

 medullary strands. The developing stelar system does not pass through a 

 siphonostelic phase as in most ferns with numerous vascular strands; but, 

 like certain Nymphaeaceae, breaks up immediately and becomes polystelic. 

 The sporangia are large, and have an imperfectly developed annulus. Miss 

 Ford considers Ceratopteris to be closely allied to the Polypodiaceae, and 

 also to show less marked affinities with the Marsiliaceae.— E.G. Jeffrey. 



RosENviNGE" contributes a paper on spiral position of leaves in several 

 species of Polysiphonia. It is somewhat polemic, being directed against 

 oeckt. His figures are meager for the immense amount of mechanics 

 involved. He refutes Schwendener's contact theory, and makes clear the 

 fact that the position of the leaf depends upon the position of the daughter 



Development of the embryo sac and embryo of Castalia odorata and Nymphaea 

 advena. Bull, Torr. Bot. Club 29 : 211-220. pis. 12-13. 1902. 



"The anatomy of Ceratopteris thalictroides (L.)i Annals of Botany i6:95-i2l. 

 /^- 6. 1902. 



RosENviNGE, L, KoLDERUP, Ueber die Spiralstellungen der Rhodomelaceen. 

 lahrb. Wiss, Bot, 37 : 338^364. pi. 6, 1902. 



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