FUNGOID PESTS OF CULTIVATED PLANTS. 16B 



Lemon and Orange Scab. 



Cladosporium Citrl (Mass.). 



This mould is developed on the leaves and fruit of Orange and Lemon 

 in a manner analogous to the scab on Apples (Fnsicladium), and is very 

 injurious to Orange trees in Florida and Louisiana. (Mass. PL Dis. 

 p. 310.) 



Another and similar mould attacks Orange leaves in Italy. This is 

 Cladosporium elegans (Penz.). 



The "foot-rot " of Orange and Lemon trees, in South Europe and the 

 United States, is attributed to Fusarium Limonis (Briosi). 



Orange Anthracnose. 

 Glccosporium Hendersonii (B. & Br.), PL XIV. fig. 14. 



This parasite of cultivated Oranges was described by Berkeley some 

 years ago, but does not appear to be common. It occurs on the under 

 surface of the leaves, and the pustules are scattered without forming any 

 definite spots. 



The conidia, which are produced in the pustules, are oblong (12^-15 jjt 

 long), and the mass, when extruded through the ruptured cuticle, is 

 slightly coloured. 



B.&Br. Ann.N. H. No. 1702 ; Sacc. Syll. hi. 3673 ; Grevillea,\i. 126. 



There are seven or eight other species of Anthracnose which attack 

 Orange leaves, especially in the South of Europe, bat they are not re- 

 corded as British, and leaf-spots, of several genera, almost too numerous 

 to mention, but our interest in Orange culture is comparatively small. 



One Italian leaf-spot, Spharclla Gibelliana (Pass.), develops asci and 

 sporidia on living Orange leaves. 



Orange-leaf Anthracnose. 



Several species of Anthracnose have been recorded as attacking the 

 foliage of Orange and Lemon trees in conservatories. 



Glmosporium Hespcridearum forms large bleached spots on the leaves, 

 on which the pustules are gregarious and numerous. The conidia are 

 cylindrical, straight, rounded at the ends, without guttules (11-18 x 5-6£ //.). 

 This has been detected only in Italy. 



Another Italian species is Glceosporium dcprcssum, occurring also on 

 dry spots on fading leaves, with the pustules scattered on the under sur- 

 face. The conidia are elongated elliptical (7-8^ x2J>-4^), produced upon 

 rather long fasciculate basidia (20-21 /j long). 



The Belgian species has large irregular greyish-brown spots, without 

 definite margin, on which are seated the small whitish pustules. The 

 conidia are ejected in flesh-coloured masses, and very minute (8 /« long). It 

 is called Glceosporium Aurantiorum. Another Italian species (found 

 also in France), Glceosporium inlermedhwi, has the pustules pointlike, 



M 2 



