GLOSSARY 

 A 



acervuli. Small groups of mycelial tufts upon which 

 fungus spores are formed. 



^cidiospores. Spores of the rust family formed in an 

 aecidium. 



sodium (ascium). A cup-shaped body in which are 

 formed the spring spores of certain rust fungi. 



aerobe. Organism requiring air, more especially oxygen. 



ammonification. The formation of ammonia at the 

 expense of other forms of nitrogen compounds, by 

 the action of micro6rganisms upon organic sub- 

 stances. 



ammonifiers. Microorganisms capable of transforming 

 nitrogen compounds into ammonia. 



amceboid. Like an amoeba, the creeping movement 

 of which is made possible by appendage-like bodies. 



antheridium. The male sexual organ in fungi. 



apical. Terminal formation at the point of any struc- 

 ture. 



arthrospores. Whole vegetative cells of either bac- 

 teria or fungi, which by a thickening of their walls 

 become resting spores. 



ascospores. Spores formed in an ascus. 



ascus. A sac-like structure in which the winter spores 

 of certain fungi are formed. 



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