FUNGI 193 



most of them out of our carpets and homes with a vacuum 

 cleaner, but this would not be worth our while if it were 

 not for the fact that they are associated in the dust with less 

 reputable bacteria. 



There is just one point that we should learn in a way we 

 can never forget. The skins of fruits, of course, are covered 



Fir,. 94. Experiments in growing yeast 



1, yeast planted in molasses 1 part, water 5 parts, kept at room temperature: 



'_', same, kept in dark; :>, planted in filtered, boiled, or distilled water; 4, same 



as 1, not planted : r>. same as 1, kept in cracked ice 



with yeasts and with spores of molds. This fact is related to 

 one of the large industries of the world the picking, hand- 

 ling, and marketing of fruits. 



KxiM.i.'i.MKXT 1. Have the class collect a number of the fruits avail- 

 able at the season. Scrape the surface lightly with a sharp, clean scalpel 

 point or knife-needle (or wash with a fine brush into a drop of water on 



