SECT. II. DISEASES. 



morbid swelling of the ear, and not at all connected 

 \vith the growth of a Fungus* 



It is said to be effectually prevented by steeping 

 the grain before sowing in a weak solution of arsenic. 



But besides the disease called smut there is also 

 a disease analogous to it, or a different stage of the 

 same disease, known to the farmer by the name of 

 Bags or Smut-balls, in which the nucleus of the seed 

 only is converted into a black powder, whilst the 

 ovary, as well as the husk, remains sound. The ear 

 is not much altered in its external appearance, and 

 the diseased grain contained in it will even bear the 

 operation of threshing, and consequently mingle 

 with the bulk. But it is always readily detected by 

 the experienced buyer, and fatal to the character of 

 the sample. It is prevented as in the case of smut. 



SUBSECTION in. 



Mildew. Mildew is a thin and whitish coating 

 with which the leaves of vegetables are sometimes 

 covered, occasioning their decay and death, and in- 

 juring the health of the plant. It is frequently 

 found on the leaves of Tussilago Farfara, Humulus 

 Lupulus, Corylus Avellana, and the white and yel- 

 low Dead-nettle. It is found also on Wheat in the 

 shape of a glutinous exudation, particularly when 

 the days are hot and the nights without dew. 



Willdenow says it is occasioned by the growth of 

 * Smith's Introd. p. 34$. 



