Morphologie u. Teratologie. — Physiologie. 523 



calicinal est remplace' par un verticille de 2 — 6 feuilles plus ou 

 moins pennatipartites, la corolle se de'colore et se transforme 

 en une gafne courte, membraneuse, portaut des e'tamines steriles,, 

 les stigmates sont remplaces par 1 — 6 feuilles simples ou 

 pennatipartites; eniin des bourgeons adventifs peuvent apparaitre 

 ä divers niveaux sur l'ovaire. Lignier (Caen). 



JODIN, Dr. H., Sur lastructure et le developpement 

 de l'ovaire chez les Nolane'es. (Assoc. frane. Congr. 

 d'Ajaccio. 1902. p. 438.) 



L'ovaire du Nolana prostrata est, lorsqu'il est jeune, reguliere- 

 ment forme' de 5 carpelles reunis en un long style ä leur partie 

 superieure. Ces carpelles, qui sont coalescents entre eux et 

 avec le receptacle dans leur moitie infe'rieure, renferment chacun 

 quatre ovules. C'est la croissance ulterieure qui, en portant 

 surtout sur les ovules, rend ceux-ci saillants et leur donne 

 l'aspect d'autant de nucules entourant un style gynobasique. 



Lignier (Caen). 



Ewart, A. J., On the Physics and Physiology of the 

 Protoplasmic Streaming in Plants. (Proc. Roy. Soc. 

 vol. 69. 1902. p. 466.) 



The energy of movement is generated in the moving layers 

 themselves, and these are retarded by friction against the non- 

 moving ectoplasm to an extent determined by their own viscosity, 

 and to a much less extent by friction against the cell-sap 

 which is passively carried with the stream. The velocity of 

 Streaming is largely dependent upon the viscosity of the 

 protoplasm. 



Gravity exercises little or no influence upon Streaming in 

 small cells, and only a very slight indirect action on Streaming 

 in large ones. The velocity of floating particles of greater or 

 less density than the plasma may be distinctly affected by 

 gravity, which indicates that the viscosity of the Streaming 

 plasma is comparatively low. As the temperature rises within 

 certain limits (0° to 45 u or 50° C), the viscosity of the plasma 

 decreases, and a large part of the increased velocity is due to 

 this cause alone. 



The direction of Streaming is mainly determined by internal 

 factors: in rotating cells a reversal is only possible in certain 

 cases and under special conditions. Changes occur spontaneously 

 in cells exhibiting circulation. The total resistance during 

 circulation is greater than during rotation: hence, unless the 

 velocity increases considerably, a change from the former to 

 the latter, in consequence of Stimulation, is not due to increased 

 energy of Streaming but to a change in the configuration of 

 the protoplasm. 



The energy for Streaming can be derived either from aerobic 

 or anaerobic metabolism. Certain species of Chara and Nitella 



