744 



TEXTBOOK OF BOTANY 



Fig. 372. Alder thicket on glacial drift two to three feet thick overlying stagnant 

 ice of the Allen Glacier, Copper River, Alaska. The man in the center of the 

 picture is facing the exposed ice front. Photo by W. S. Cooper. 



Fig. 373. Remnants of a western hemlock-Sitka spruce forest buried under 200 

 feet of gravel about 1000 years ago. They have been uncovered recently by flood 

 water from a rapidly melting glacier farther up the valley. These tree trunks and 

 the plants of the forest Hoor are in a perfect state of preservation. Photo and data 

 from W. S. Cooper, Fourth Expedition to Glacier Bay, Alaska, 1935. 



