FUNGI 27 



be recommended for the purpose of checking disease, especially 

 in those instances where the inoculating bodies are present in 

 t}ie form of testing-spores or sclerotia in the soil. 



Shade trees are commonly employed in tropical countries 

 for the purpose of affording shelter to plants under cultiva- 

 tion, especially in the case of tea, coffee, and cacao. 



This is a subject worthy of much more attention than 

 it appears to have received up to the present, although 

 Dr. Watt has some remarks to the point in connection 

 with tea culture in India. 



There is grave danger of introducing or perpetuating 

 disease unless great care is exercised in the selection of 

 shade trees. 



As previously stated, parasitic fungi as a rule confine 

 their attacks to closely allied plants, or at most to plants 

 belonging to the same Order. For this reason it would not 

 be advisable to utilise as shade trees such as are closely 

 allied to the plants under cultivation. 



Another point of importance is to ascertain whether 

 fungus parasites likely to attack cultivated plants are 

 present on wild plants in the jungle or forest. 



Hemileia canthii. Berk, and Broome, infests Plectronia 

 campanulata, Bedd. (= Canthium campanulatum, Thwaites), 

 a wild plant common to Ceylon and India, and the parasite 

 on the leaves of this plant is so close to the Hemileia vasta- 

 trix, Berk., the coffee leaf disease, that it is doubtful 

 whether the two parasites are not identical, the minute 

 differences observable being due to difference of host. 

 Again, Hemileia woodii, Kalchbr. and Cooke, appears to be 

 not uncommon on two small trees allied to the coffee 

 plant, Vangueria tn/austa, Bruch, and Vangueria latifolia. 



