350 SUMMARY OF CUKRENT RESEARCHES RELATING TO 



He applied the practical test of spraying one row of plants and leaving 

 another alone, with tlie result that the unsprayed plants all rotted from 

 the attack of the fungus. During a very cold and very wet summer, he 

 found that the normal amount of spraying was insufficient as the solution 

 was washed ofif by the heavy rains and the fungus got the upper hand. 

 In such a season he recommends extra spraying and with a stronger solu- 

 tion than that usually employed. 



G. Lustner * publishes an account of work done at the plant patho- 

 logical research station at Gesenheim. An unusually virulent attack of 

 the vines by Peronospnra occurred. The infection of the berries spread 

 evidently from the stalk. He discusses at length a disease of cherry- 

 trees and alders on which species of Valsa were found. He concludes 

 that the trouble was due to soil conditions, and the fungi were sapro- 

 phytes. 



R. Solla t gives a resume of reports sent as to Italian plant diseases. 

 A. Noelli contributes a list of 200 fungi from the neighbourhood 

 of Turin, many of them parasites and hurtful to the higher plants. 

 G. B. Traverso records those occurring on the trees and herbs in the 

 Como district, on oak, chestnut, almond, etc. 



E. Barsali % found Folyporus Schweinitzii at the base of a pine-tree 

 near Pisa. He reports also various Uredineaj on cereals, beans, onions, etc. 



Amed. Berlese § found a fungus growing on the shield-louse, 

 Geroplastes Rusci. He isolated it and grew it on various media. He 

 determined and named the fungus Oospora Saccardiana. 



Reproduction and Regeneration in Fungi.|l — Paul Kohler reviews 

 the work done on this subject by various authors, proving that isolated 

 parts of a fungus plant could grow and produce fruits in various species. 

 He then proceeds to give the result of his own researches. In Mucor 

 stolonifer he found that if a portion of the mycelium were wounded, the 

 damaged part was cut off by a cell-wall. If the hypha were divided 

 each part continued to live and grow, reproducing the whole plant. 

 Sporangiophores and sporangia also continued to develop when they had 

 reached an advanced stage and the columella was formed. At an earlier 

 stage they failed to grow when cut off and placed in the culture solution. 

 Stolons and rhizoids were unable to grow when separated from the 

 plant. Phycomyces nitens was found to be more capable of regeneration 

 than Miicor ; the wounded parts proliferated instead of being cut off by 

 a cell-wall. 



With Penicillium yJaucum and Aspergillus niyer it was found that 

 any cell was capable of growing and reproducing the plant. 



Experiments were also undertaken with the higher fungi — 

 Agaricus campestris, Coprinus stercorarius, etc. It was found that in 

 many of the Agaricineaj and in Coprinus all living cells are capable of 

 growth, and that cells of the cap, stalk, hymenium, and surface possess 

 the capacity of regeneration and reproduction. Among the Polyporete 

 it was found that for further growth the fungus must remain on its 

 substratum, and in Xylaria hypoxylon only the cells near the growing 



* Zeitschr. Pfianzenkr., xvi. (1907) pp. 323-7. 



t Tom. cit , pp. 328-9. J Bull. Soc Bot. Ital., 1906, pp. 93-8. 



§ Zeitschr. Pflanzenkr., xvi. (1906) p. 329. 



II Flora, xovii. (1907) pp. 216-62 (10 figs.). 



