Descendenz u. Hybriden. — Physiologie. 325 



clation gardent leurs proprietes nouvelles quand on les reproduit 

 par boutures. 



Pour faire acquerir im caractere ä une vigne hybride il faut la 

 greffer sur une plante possedant une seve commune avec eile 

 de teile sorte que la proportion totale de cette seve devienne 

 predominante dans l'association. On peut songer ä combiner 

 l'hybridation sexuelle et l'hybridation asexuelle pour creer des 

 typesde remplacement, modifier la pulpe du grain, faire disparaitre 

 le göut de fox, augmenter la resistance aux agents cosmiques, 

 aux parasites, etc. A. Giard. 



Mac Dougal, D. T., The origin of species bv mutation. 

 (Torreya II. 1902. p. 65—68, 81—84, 97—100.) 



A discussion of the theory of origin, of species as set forth 

 by de Vries, and of the bearing of this theory on evolutionary 

 Problems. Mac Dougal. 



MEEHAN, Thomas, Contributions to the lifehistory of 



plants, N o. 16. (Proceedings of the Academy of Natural 



Sciences of Philadelphia. LIV. p. 33—36. February 1902.) 



This posthumous paper contains two discussions: The Bartram oak, 

 in connection with Variation and hybridism; and observations on the 

 flowering of Lobelia cardinalis and Lobelia syphilitica. Trelease. 



Bain, Samuel M., TheAction ofCopper onLeaves. (Bull. 

 Agric. Expt. St. Univ. of Tennesee. Vol. XII. No. 2. April 

 1902. p. 21—108. Plates I— VIII.) 



The paper is divided into six chapters as follows; I. Poiso- 

 nous Action of Copper Solutions Introduced through theRoots; 

 II. Posionous Action of Copper on the Leaves and Certain 

 Conditions Affecting this Action ; III. Permeability of the Cuticle 

 and its Relation to the Action of Fungicides; IV. Wound Hea- 

 ling of the Leaves and Leaf Fall; V. Influence of Copper on 

 the assimilative Function of Leaves; VI. General Conclusions 

 and Practical Application of Results. While the subject is dis- 

 cussed largely from the stand point of the action of copper 

 salts on the peach, it is by no means limited to that. It is 

 shown that in the case of peach foliage the injury caused by 

 copper is of the same character whether the copper is supplied 

 in the form of a soluble salt or of the hydrate. Deliquescent 

 copper salts are especially harmful. In the matter of the 

 copper hydroxide the author comes to the conclusion that, at 

 least under the conditions which exist on the peach leaf, it is 

 sufficiently soluble to be absorbed; hence the retarding influence 

 on the poisonous effect which lime exerts, since it would tend 

 to neutralize any solvent substance exuded by the leaf. As 

 to the stimulating effect of copper on the assimilative functions 

 three plants were tested, the grape showed the greatest re- 

 sponse, next the apple, while the peach even under the most 



