HUMBLE FAMILIES IN GRAY. 1 83 



ing rough and crumbling surfaces, and so difficult 

 to identify, appear interesting only from associa- 

 tion. They are the representatives of the earliest 

 forms of vegetation, the copies and reprints of 

 Flora's ancient drawing. After the rocks had 

 been lifted from the ancient seas, or a pinch of 

 gravel-dirt was formed, then the goddess began 

 her work. With cunning fingers she hastened to 

 mount the plants, without true stems, leaves, 

 flowers or roots, wherever there was a suitable 

 matrix. The lichens depend wholly on the mois- 

 ture for their increase, they are of necessity of 

 slow and interrupted growth, but capable of contin- 

 uing many years. Their starchy nature favors 

 hibernation. As the buried tubers and corms 

 wait for the sun to warm the earth that they may 

 germinate, so these humble plants, in seasons of 

 drought, wait patiently and without apparent suf- 

 fering, for the rain or the humid air to set their 

 laggard shuttles in motion again. 



