CALIFORNIA PLANTS IN THEIR HOMES 



growing on, you will notice that you must break tough, 

 white fibres that have held them fast. Perhaps, by tearing 

 and picking apart your lichen, you can find out that much 

 of it consists of this same tough, white, felt-like mass of 

 fuzzy hairs; that is, the greater part of a lichen is fungus. 

 Probably you can find near the surface some traces of 

 bright green color. You will find little cups or saucers 

 on most of your lichens. You can see, too, how quickly dry 

 lichens absorb nearly their own weight of water. 



Now the microscope tells a wonderful story about 

 lichens. It shows clearly that the greater part of the 

 lichen is fungus, but among the interlacing threads of the 

 fungus are multitudes of tiny, green cells, called algae. 

 Each green cell is a plant that can live quite by itself. So 

 we see that a lichen is not a single plant, but it consists of 

 a big fungus that cannot make its own living and a host of 

 minute algae that can make food very fast indeed when 

 there is plenty of water; and the big, helpless fungus 

 is actually supported by these tiny mites, the algae. But 

 the algae can well afford to make food for the fungus, as 

 well as for themselves, for the fungus shelters them and 

 provides them with the moisture and the dissolved minerals 

 and gases that they need. The algae really thrive better 

 imprisoned by the fungus than when they are free and have 

 only themselves to support. So both fungus and algae 

 have plenty of food when there is moisture to be had, and 

 they can get moisture from the air when we cannot see it 

 at all. When the air is dry, they rest; and they can rest for 

 months, and then spring quickly into active life again if 

 there is rain or fog or dew. 



I4ke other fungi, the lichen fungus produces many 

 spores. They grow in tiny sacs just below the surface of 

 the little cups you saw. When these spores find a resting 

 place in a favorable spot and among suitable algae servants, 

 they grow into new lichens. You will often find lichens 



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