MANORANJAN MITRA (pl 
10. SUMMARY. 
1.~ There are several species of Acrotheciwm known on various grasses, 
but none has hitherto been reported on Pennisetum typhoideum, and the present 
species does not agree with any of those previously described. It is a new 
disease caused by Acrothecium Penniseti n. sp. 
2. It is found on ears, leaves and leaf-sheaths, and forms dirty brown 
spots with yellow margin. 
3. Conidiophores arise in clusters through the stomata and spores are 
borne apically in fascicles of 2—5. 
4, Infection can take place either through a stoma or by directly piercing 
an epidermal cell. 
5; ‘The fungus is cultivable on most artificial media but gives the highest 
development on wheat broth agar, potato juice agar, nutrient glucose agar, 
and on French-bean agar. 
6. In culture secondary sets of conidia are formed either below the tip on 
the sides of conidiophore or above by the elongation of the latter. 
7. In some media chlamydospores of a dirty brown colour are formed. 
8. The growth is best on media having the reaction between-+5 to+10 
Fuller’s scale but the fungus can withstand a wide range of reaction. 
9. The parasitism of the fungus has been proved beyond doubt by 
numerous inoculations on leaves and ears. 
10. The mycelium is both intra and inter-cellular and is found in all 
parts of the infected leaf. 
11. Cross imoculations on male inflorescence of maize were successful 
while those on Sorghum gave negative results. 
To Dr. EK. J. Butler, Imperial Mycologist, under whose direction this 
work has been carried out, is due my grateful acknowledgment for his able 
advice and criticism. 
