NOTES ON EE CENT RESEARCH. 



225 



of the two sets of results given. Marked toxic effects appear long before 

 turgor is reduced or growth checked. 



By experiments upon the influence of mixtures of the salts it was 

 found that the toxic effect of one salt can be diminished by addition of 

 another to the solution, and the diminution is much greater when a 

 different kind of kathion is added than when a new anion only is intro- 

 duced. The addition of sodium ions to a solution containing magnesium 

 ions generally reduces the poisonous effects of the latter, and calcium 

 ions added to solutions containing sodium or magnesium ions have an 

 extraordinarily beneficial influence, especially when the calcium is added 

 as sulphate. 



The authors also show that plasmolysis, which is so generally supposed 

 to be due to a reaction to physical stimuli only, can apparently be 

 prevented by altering the chemical nature of a solution without materially 

 reducing its osmotic pressure. 



The authors conclude that the effect of one kind of ion in neutralising 

 the physiological action of another kind cannot be entirely explained by a 

 consideration of the chemical changes within the solution itself ; some of 

 the effects must be in part referred to changes in the protoplasm of the 

 organisms. 



When the concentration of the solution of the salts already mentioned 

 was reduced to a certain point the toxic effect disappeared. In solutions 

 diluted still further a stimulating effect was observed, the roots of the 

 plants growing more vigorously than those of control plants grown in 

 distilled water. — J. P. 



Plant Anatomy. 



Anatomy of Leaf and Axis (Genistese) (Beih. Bot. Cent. bd. xi. 

 ht. 6, pp. 368-417). — Herr Alfred Schroeder (aus Danzig) describes the 

 minute anatomy of the Lipariece and Bossiczce in a very detailed and 

 complete manner. They exhibit very marked xerophilous characters. A 

 few possess epidermal papillae, deeply sunk stomata, or centric leaf 

 structure. As the details of some sixty-four species are fully given in 

 the paper, it is scarcely possible to make a satisfactory abstract. It seems 

 from the anatomy as if Goodia should be withdrawn from the Genistece. 



G. F. S.-E. 



Structure of Aphyllon. 



Aphyllon uniflorum, Structure and Parasitism of. By Amelia 

 C. Smith, B.S. (Contr. Bot. Lab. Phil., vol. ii., No. 2, 1901, p. Ill ; pis. 

 13-15). — The naked Broomrape is typically a North American species, para- 

 sitic on Aster corymbosus. The degeneration attendant upon its parasitic 

 habit is expressed by (a) absence of chlorophyll, (b) degeneration of bract 

 leaves, (c) loss of root-hairs, (d) reduction of the bundle system, and the 

 greater relative development of phloem than of xylem, (e) small size of 

 seed and primitive embryo, and development of this embryo within a mass 

 of precocious endosperm, which completely surrounds the embryo and 

 suspensor. 



Parasitic roots form intimate connections with host-roots, but the 

 host-roots are not entirely starved beyond the point of attachment. 



Q 



