An Ecological Study of Buckeye Lake. 51 



to the age of our oldest trees. No roots nor internal conducting 

 systems develop but the elongated hyaline cortical cells of the 

 stem and branches, and the hyaline cells of the stem and branch 

 leaves offer a system of capillaries thru which water is readily 

 conducted. At every fourth stem-leaf a fascicle of branches 

 from 2-3 inches long, tapering and very slender hang down, 

 close appressed to the stem, around which they form an absorb- 

 ing and water-conducting mantle. The leaves of both stem and 

 branches are but one layer of cells in thickness. They are con- 

 vex, imbricated and closely invest the axis, forming thus nar- 

 row spaces thru which water passes by capillarity. The hyaline 

 cells of stem and leaves act as water reservoirs ; they are large, 

 elongated cells whose walls are strengthened by spiral thicken- 

 ings. The close massing of the fronds; contributes largely to the 

 sponginess of the Sphagnum turf. 



The capacity of Sphagnum for absorbing water is enormous. 

 Lesquereux found that air-dry Sphagnum in contact with water 

 absorbed seventeen times its own weight. Dueggeli obtained re- 

 sults of 18.5 to 22.96 times the weight of Sphagnum. Because 

 the external cells so readily absorb and conduct water, the plant 

 is independent of a water supply from the soil and the shoots 

 continue to live and grow. The result is a characteristic eleva- 

 tion of the surface of the bog from the margin to the center, 

 giving rise to the term High moor of the German writers. 

 Schimper^^ states that the center may lie four meters higher than 

 the border. Ganong-'' ^° made a similar observation on peat 

 bogs in New Brunswick which were from 14-15 feet higher in 

 the center than at the margin and still rising. 



In Cranberry Island the meadow is so interrupted by masses 

 of shrubs that this uniform elevation does not occur; but it is 

 noticeable in smaller areas. The Sphagnum has built up hum- 

 mocks or little mounds from 3 to 6 or 7 decimeters (12-24 01* 3^ 

 inches) high around the base of isolated shrubs, clumps of 

 ferns, the border of a thicket and the margin of small pools, and 

 in some areas as in the northeastern portion of the meadow, 

 these hummocks are very frequent where there are no shrubs. 



