THIELAVIOPSIS PARADOXA. 573 



(3) In estimating the value of a fungicide, by testing the 

 germination of spores after they have been submitted to its 

 action, it is necessary to keep tlie transfers under observation 

 for several days, even in the case of spores which normally 

 germinate within a few hours. 



(4) In the case of thick- walled spores, the fungicidal value 

 of copper sulphate is small. 



(5) Spores of the same fungus vary enormously in their 

 power of resisting the action of toxic agents, so much so that 

 it is not possible to find an approximately constant time in 

 which the spores would be killed by immersion in a solution 

 of given percentage. It is only possible to give a maximum 

 limit, and this could only be obtained by an extended 

 series of tests. Single experiments may be quite 

 misleading. 



Bibliografhy . 



1. de Seynes, J. Sur le developpement acrogene des 



corps reproducteurs des Champignons. Oompt. 

 Rend. Paris, CXI. (1886), pp. 933, 934. 



2. de Seynes, J. Recherches pour servir a I'histoire 



naturelle des vegetaux inferieurs, III,, Paris (1886).. 

 Pt. 1, De la formation des corps reproducteurs 

 appeles acrospores. 



3. de Seynes, J. La Moisissure de 1' Ananas. BuU. Soc. 



Myc. France, IV. (1888), pp. XXVI.-XXX. 



4. Went, F. A. F. C. De Ananasziekte van het Suikerriet. 



Meded. van het Proef station West Java (1893). 



5. Massee, G. Sugar Cane Disease. Kew Bulletin, No. 79, 



July, 1893, pp. 149-152; No. 87, March, 1894, 

 pp. 81-84. 



6. Massee, G. On Trichosphceria sacchari. Annals of 



Botany, VII. (1893), pp. 515-532. 



7. Prillieux and Delacroix. Sur une maladie de la canne k 



Sucre produite par le Coniothyrium melasporum 

 (Berk.) Sacc. Bull. Soc. Myc. France, XI. (1895), 

 pp. 75-84. 



8. Went, F. A. F. C. Notes on Sugar Cane Diseases. 



Annals of Botany, X. (1896), pp. 583-600. 

 6(11)10 (74) 



