FUNGUS OF TUENIP DISEASE. 



Oidium Balsamii Mont. 



A.B. — Shows the thickness of the lamina of a turnip leaf with 

 the Oiclium growing upon both the upper and lower surfaces. 



0. — One of the stomato, or organs of transpiration, seen in 

 section on the under side of leaf choked over with the spawn of 

 the fungus. 



D.D. — Cellular tissue of the leaf. 



E. — Spiral vessels belonging to a veinlet of ditto, all enlarged 

 360 diameters. 



F. — A germinating spore on the epidermis of leaf (0, stomate 

 or organ of transpiration). 



G. — Young spore on the tip of thread which has emerged from 

 the germinating spore, enlarged 480 diameters. 



