344 PLANT DISEASES 



attacks branches it becomes an undoubted parasite, and 

 kills the parts attacked. As the disease on branches in all 

 probability in many instances originates from infection by 

 reproductive bodies formed on leaves in the first instance, 

 its presence under any circumstances should be regarded 

 with suspicion. Dr. Watt states that in the present state 

 of knowledge regarding this blight the following remedial 

 measures seem worthy of consideration ;- — 



ist. Where shade trees are found to cause the leaves of 

 tea underneath to be coated with the grey lichenoid 

 formation and the orange-red algal patches, the trees in 

 question should be removed. 



2nd. Where the leaves of any plot of tea are found to 

 be abnormally attacked by the alga, they should be plucked 

 off and destroyed, or washed with Bordeaux mixture. In 

 neighbourhoods liable to the form that invades the stem, 

 every orange-red spotted leaf should be carefully removed 

 and destroyed. 



3rd. The seedlings in the nursery, if found to manifest 

 the orange-red spots, should be washed with the above- 

 mentioned fungicide, and in districts liable to the stem 

 invasion they should be dipped into a tub of that fluid at 

 the time of transplantation. 



Cunningham, Trans. Linn. Soc. (Boi.), ser. 11. vol. i. 

 p. 301, pi. xlii. xliii. (1879). 



Marshall Ward, Trans. Linn. Soc. {£ot.), ser. in. vol. ii. 

 p. 87, pi. xviii. xxi. (1884). 



Karsten, Ann. Jard. Bot. Buitenzorg, 1891, pi. iv.-vi. 



Cephaleurus parasiticus, Karsten. — Common on leaves of 

 Calathea and Pandanus at Buitenzorg, Java. The epider- 



