W. MCRAE 26^ 



penetrated. P. Faheri infected imbniised cacao fruits in two or tliree days 

 producing copious sporangia and resting conidia on the 5th day and gradually 

 blackening the surface till by the 7th or 8th day the whole fruit was black. The 

 bruised cacao fruit showed infection of P. Meadii on the 4th day, and of P. Fdheri 

 the 2nd day. The hyphse produced from the 4th to the 20th day on the surface 

 of the former did not form sporangia in situ, yet several times during the interval 

 they produced them in two days after being placed in water and in culture 

 media. The two mibruised and the bruised control cacao fruits were still 

 fresh and healthy on the 2dth day. Inmiediately afterwards twelve more 

 cacao fruits were put up as before and not bruised. Six were inoculated from 

 a culture of P. Meadii by placing pieces of the French-bean-agar containing 

 mycelium with actively discharging sporangia in a drop of water on a groove 

 on the side of each fruit. One showed discoloration on the 4th day. Next 

 day the discoloration was marked and hyphae were present. Oji the 9th day 

 the discoloration had passed aU romid the fruit but not quite to the ends, and 

 hyphae were present in little masses all over. The hyphae were close to the 

 surface, much branched and irregularly swollen. Till the 12th day no 

 sporangia were produced in situ, though as before when the mycelium was 

 placed in water, sporangia were produced. The other five fruits were healthy 

 after 20 days. The inoculative material when pliaced in water continued 

 growing, and sporangia discharged, so that it was alive aU the time it was 

 on the fruits, and the surface of the fruits was always sufficiently moist to 

 allow of the growth of the fungus. Five of the control fruits were healthy 

 after 20 days; the sixth became mouldy with Eurotium and Aspergillus on 

 the 12th day, owing doubtless to the fact that the water in the potato-dish 

 dried up and allowed access to the open air dmring my temporary absence from 

 the laboratory on other work. Thus mider exactly similar conditions Hevea 

 fruits were infected readily both by P. Faheri and P. Meadii, while cacao fruits 

 were infected readily by the former and with difficulty by the latter. 



Cacao is not grown in the rubber districts of Sovith India, and there are 

 no plants on estates. There may be one or two plants gro\Mi in gardens in 

 places like Trivandnmi and Calicut, and there are a few in a small Govenmaent 

 garden at Kallar at the foot of the Nilgiris, but aU these places are far away 

 from the estates. In the latter case the cacao plants are not attacked by 

 P. Faheri, and the few acres of Hevea in the garden are not attacked by P. Meadii. 

 Thus it seems impossible that Hevea could be infected from cacao in South 

 India. No other trees or plants have been observed to have a similar fruit-rot 

 or leaf-fall. Tme, I have comparatiNely few opportmiities of observing trees 



