PLANTS WHICH CA CUJi' DEOA Y 



397 



on which they grow l Can foods be protected against 

 tliem in the same way as against bacteiia ? ^ 



An immense amount of damage, amounting in the 

 United States alone to a great many 

 miUions of dollars each year, is done 

 to crops by the Smuts, Rusts and 

 Mildews. For this and other reasons 

 it is worth while to devote some 

 study to these plants, in order that 

 we may more clearly understand their 

 mode of life and the best remedies 

 against theui. 



The common Corn-smut begins to 

 appear in the leaves when the plant 

 is three or four feet high, forming 

 small white spots raised above the 

 surface of the leaf and somewhat 

 wrinkled (frequently surrounded by a reddish dis- 

 coloration of the leaf). Later on they turn black 

 (or disappear altogether) . The Smut appears on 

 the stalk, inside the sheathing base of the leaf, near- 

 the joint or node. It also appears in the form of 

 pustules scattered through the male flowers or tas- 

 sel ; it also appears on the ears, covering them 

 partially or completely, forming white masses with a 

 peculiar soft, silvery luster ; later these burst and 



1 A very good method of sealing jellies is to pour melted parafifin on top : 

 the heat kills the Moulds and bacteria while the paraffin seals the tumbler her- 

 metically. 



2!il. Green Mould of cheese, 

 etc., showing the man- 

 ner in which the spu7'es 

 ts) itre borne. 



