515 



asci well matured, it may be removed entirely by pressure, as repre- 

 rented at A. A power of about 600 diameters is necessary to see it 

 properly. 



An ascus measures about the one thousandth of an inch in diameter, 

 and is about seven times its diameter in length. 



If an ascus is treated with an alcoholic solution of iodine, containing 

 a few drops of nitric acid, its nitrogenous matter becomes stained of a 

 dark amber while the sporidia retain their natural color. The asci will 

 frequently exhibit, when treated with acids and alkalies, an expanded 

 membrane of very delicate texture and quite transparent, as exhibited 

 atT. 



The true cause of this disease is unknown at present. My future in- 

 vestigations will be'principally confined to its mode of propagation. In- 



