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spots were counted on a square centimeter of a badly infected leaf and 
44 spots on a square centimeter of one slightly infected. In the grape 
fruit only 130 spots to the square centimeter were found on a badly 
infected leaf; these were partly confluent, forming an almost continu- 
ous blotch. Where the spots are very abundant they frequently 
run together, forming large, irregular, dark brown blotches. This 
frequently occurs on all species of citrous trees affected with the disease, 
and is found on stems, leaves, and fruits. On the fruits in particular 
this is of frequent occurrence. As the fruit ripens, the blotches, which 
_ are hard and brittle, sometimes become considerably checkered and 
fissured, similar to the cracking of mud in drying. 
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Fig. 6.—Melanose on sweet orange twigs. 1, healthy; 2, diseased. 
| The spots are to some extent formed on both surfaces of the leaf, but 
are much more abundant on the upper surface. This character is more 
particularly noticeable in the grape fruit than in other species of cit- 
i} 
frus. On grape fruit the spots are almost wholly limited to the upper 
‘surface. In the common sweet orange and sour orange they occur 
abundantly on the lower surface, but are still more numerous on the 
upper surface. On the different portions of the fruit and young stems 
the spots are apparently uniformly abundant. This malady is most 
i severe on the lower portions of the tree, but the characteristic spots 
|are also found on the leaves and twigs in the tops of large trees, nearly 
30 feet from the ground. 
