72 SCIENTIFIC REPORTS OF THE AGRICULTURAL RESEARCH 



were now subjected to a more critical examination. The 

 field specimens from Dacca and Pusa both agreed with the 

 infected stems of 1917 in the character of the pycnidium 

 and spores which it contained. While this resembled an 

 immature stage of D. Corchori very closely it was obvious 

 that, in the case of the 1917 infections, since they were at 

 the time of this later examination nearly a year old, 

 if the pycnidia were those of D. Corchori they 

 should ' contain mature bicellular spores. In all cases, 

 however, the spores were hyaline, oval and unicellu- 

 lar, and the possibility that this pycnidium was not 

 an immature condition of D. Corchori but was a separate 

 fungus, perhaps a stage in the life-history of the sclerotial 

 fungus, had to be investigated. Measurements showed that 

 the spores from the infected stem of 1917 were 16/x — 33/u. 

 X5/U. — 9ja. In the case of specimens collected in the field 

 in Pusa the measurements were 16//,— 25/^x7/* — dfx, and in 

 specimens from Dacca 20/x— 28//,x7/u— 10/x. The spores 

 of Diplodia Corchori average 24/axl2/*, between the limits 

 20/x— 29/xxIO/a— 15/*; while therefore the spores of D. Cor- 

 chori are twice as long as broad, those of the new pycnidium 

 are about the same length but narrower. This distinction 

 is not sufficiently marked to enable these spores to be readily 

 distinguished from those of an immature pycnidium of D. 

 Corchori, but since the former never become dark coloured 

 or bicellular they can easily be distinguished, provided the 

 age of the infection from which they are taken is known 



The question whether this new pycnidium was a stage 

 in the life-history of the sclerotial fungus, identified in 

 previous communications as R. Solcmi, could only be settled 

 by culture work. Since this work is in progress at the 

 time of writing, it is possible that the conclusions put for- 

 ward here may be modified in the light of subsequent know- 

 ledge. Infections were carried out with a pure culture of 

 the sclerotial fungus, isolated in Dacca, on four jute plants 

 in Pusa. All these plants developed sclerotia and also 

 pycnidia, containing spores measuring 16 — 24^x7 — 9/>u 

 Cultures were obtained on agar from single spores and from 



