Eumycetes. — Pflanzenkrankheiten. 347 



of six months, from December 1912 to June 1913, by the transfer 

 of infection once a month. P. coronijera was also cultured for a 

 period of eight months, from September 1912 to May 1913, with 

 transfer of infection once a week. During this period the rust went 

 through 37 generations of the uredostage. No decrease in the degree 

 of infection secured resulted from such continuous culture. 



2. The average degree of infection maintained in mass cultures 

 was approximately 200 pustules per plant. The largest number of 

 pustules counted on an individual plant was 996. 



3. P. coroYiifera does not self-propagate to any extent even when 

 abundant host material is supplied and a constant humidity of 93 

 per Cent is maintained. 



4. High humidity is the essential factor in securing successful 

 inoculation with uredospores of P. coronifera. No infections resulted 

 when cultures were exposed in an atmosphere of 75 to 80 per cent 

 of humidit3^ and at 93 per cent only 6 per cent of the normal 

 degree of infection was obtained. Normal infections were secured 

 only when cultures were covered with a bell jar for twenty-four 

 hours subsequent to the application of spores. 



5. The rate of development of P. coronifera increased with tem- 

 perature increase. A decrease in the normal incubation period of 

 five days, or 41 per cent, was produced in the "stove" where the 

 temperature ranged from 20° to 30° while the ränge at which the 

 normal cultures were grown was 14.5° to 21°. 



6. Total light exclusion either early or late in the incubation 

 period checks the development of P. coronifera and results in an 

 almost complete cessation of growth. 



7. Uredospores of P. coronifera when stored atroom temperature 

 gradually lose their capacity for germination. A 0.2 per cent ger- 

 mination was obtained after storage of eighty-four days. 



Jongmans. 



Janssens, F. A., E. van de Putte et J. Helmsmortel. Le chon- 

 driosome dans les Champignons (Notes preliminaires). 

 (La Cellule. XXVIII. p. 448-452. PI. 1, 2. 1913.) 



L'appareil mitochondrial a ete fort peu etudie dans les plantes 

 inferieures. II n'y a dans la litterature qu'une courte notice de 

 Guillermond ä ce sujet et les auteurs ne pensent pas qu'il existe 

 dans la litterature du chondriosome des donnees plus precises con- 

 cernant les Champignons. 



La premiere notice traite du chondriosome dans les asques 

 de Pustularia vesiculosa. On trouve l'appareil mitochondrial dans 

 les asques ä tous les Stades de leur evolution jusqu'ä la formation 

 des spores. Le chondriosome de l'asque est une partie fort impor- 

 tante de son protoplasme, qui passe entierement dans les spores, 

 lors de leur formation. 



La deuxieme notice contient des remarques sur le S5'sieme 

 mitochondrial dans les Saccharontycetes. Les auteurs n'en donnent 

 pas encore des details. Leur premier but etait de convaincre le 

 lecteur de l'existence d'un chondriosome dans les saccharomycetes. 



Jongmans. 



Baccarini, P. und G. Bargagli-Petrucci. Prime ricerche 

 sulla malattia del Trifolium pratense {Bologn'ino) c\i\a.n\Sita 

 „incappucciamento" II. (Atti della Reale Accad. econom.- 



