POTATOE GANGRENE AND OTHER DISEASES. 109 



X 



die. The potatoes are generally smaller than a nutmeg* 

 of a rusty-red color, and unwholesome for food." 



(434.) " The corrupted potatoes are those in which the 

 vegetative power is nearly destroyed. These never ap- 

 pear above ground. The sets may be found at Michael- 

 mas with the same appearance as when they were planted, 

 with a few small potatoes attached to them."* 



(435.) Putsche. and Vertuch state "that the plants 

 which are affected by this disease have an extremely 

 meagre appearance. The stem is unbranched, brownish- 

 green, or mottled, and here and there sprinkled with rusty 

 spots, which penetrate to the pith ; so that it is not white, 

 but rust-colored, or sometimes black. The upper surface 

 of the leaves is not so smooth as usual, but rough, wrinkled, 

 curled, or crumpled. The leaves are far more sessile 

 than usual, and not of an uniform brownish or dark green, 

 but spotted. The passages for circulation, imbibition, and 

 respiration, are none of them in a healthy state. The 

 pith is often discolored or dried up, even in the young 

 shoots. The starved plant often perishes early in autumn, 

 when the tubers should be making their most rapid 

 growth. These tubers are scanty and tasteless, juicy and 

 almost unfit for food. Even the color of the outer coat of 

 the tuber is changed. The same tuber is in parts brown, 

 in parts of a dirty yellow, and sometimes the two tints run 

 into each other. Some sorts of potatoe are more subject 

 to the disease than others : it is more prevalent in flat 

 countries than in more elevated districts."")" 



(436.) From these descriptions, { am much disposed to 



* Trans. Society of Arts. 



f Martius, quoted by " Gardener's Chronicle." 



