E. M. DoidCtE 55 



to be attacked by antliracnose {Colletolrichum gloeosporioides) which 

 causes discoloured spots on the fruit not very widely differing in 

 appearance from those caused by the bacillus. They are different 

 in colour however, not conspicuously sunken, and can be readily 

 distinguished when the pinkish spore pustules begin to develop. 



During November and December of this year (1915), after this 

 article was practically completed, Mr J^ole Evans, the Ohief of this 

 Division, made a personal inspection of the orchards in the infected 

 areas. At that time there was little or no fruit on the trees so that 

 his inspection resolved itself into a search for the disease on branches 

 of trees and nursery stock. 



Branch infections were very plentiful in the orchard at Simondium 

 where the disease was first detected, in an orchard near Gillie's Siding, 

 and one in Zuider Paarl : at Simondium the organism attacks stems | to 

 1 inch in diameter. At the Elsenburg Agricultural College, the nursery 

 stock has been severely attacked but no signs of the trouble were found 

 in any of the other nurseries which were inspected. 



He saw no evidence in the orchards of the Clanwilham, Piquetburg 

 or Montagu Districts. It is apparently confined at present to the 

 valleys of the Groot and Klein Drakenstein and the Berg River Valley ; 

 in this area the fruit has been attacked on a number of farms, but branch 

 infections have only been detected in the localities mentioned above. 



From field observations it would appear that the leaf is attacked 

 first and that the disease is then communicated to the stem through 

 the leaf stalk. As soon as the petiole and neighbouring stem tissues 

 are invaded the leaf falls, and this would account for the fact that very 

 few leaf infections were found on branches sent for examination. 



Signs of the Disease. 



The disease has been found occurring in nature on lemons of the 

 Mediterranean type, navel oranges and naartjes, the term "naartje" 

 including both Mandarins and Tangerines. It has been induced by 

 artificial inoculation in lemon, orange (three varieties), naartje, shaddock, 

 grape fruit, citron and sour and sweet hmes. 



In describing the appearance of affected parts, and the cultural 

 characters of the organism, the colours named have been compared as 

 accurately as possible with those in Ridgway's polor Standards and 

 Nomenclature (^). 



It was first noticed in Geneva lemons, on which it forms discoloured 

 sunken spots varying from 1 to 3 mm. in diameter: more frequently 



4—2 



