SHOWING MILDEW. 47 



of a small penknife, and laid on a strip of 

 glass. Moisten this with a little drop of water, 

 and cover it with a small fragment of the very 

 thin glass sold by opticians for such purposes. 

 Place it on the stage of the microscope, show 

 the light through it, and look at it with a quar- 

 ter or eighth of an inch achromatic. The 

 structure of the spores, the division of the 

 chambers, the stalks, and every part of them 

 will become distinctly seen, just as they are 

 depicted in the second drawing. The observers 

 would become by these means perfectly ac- 

 quainted with this fungus. 



It is a common error to say that wheat 

 which often appears covered with a black 

 sooty fungus, dusting the ears all over, and 

 accompanied with signs of general decay, is 

 mildewed. Although this dust is a fungus, it 

 must not be confounded with puccinia. Its 

 botanical name is the cladosporium herharum^ so 

 called from the Greek word KXaSog, {klados,) a 

 branch, because the spores are terminal on small 

 and pointed branches. This fungus is undoubt- 

 edly always accidental to some previous disease, 

 and is only superficially attached to a decompos- 

 ing plant, while the ear appears as represented 

 in the next page. There is no symptom of 



