640 



TEXTBOOK OF BOTANY 



Fig. 293. Moss-covered terrain in a hemlock ioicst on a terminal moraine at the 

 mouth of Glacier Bay, Alaska. The moraine was deposited 150-200 years ago and 

 the maximum age of the trees is 110 years. Photo by W. S. Cooper. 



Fig. 294. A mat of the common fern moss (Thuidium) . Photo by E. S. Thomas, 



Ohio State Museum. 



