Minnesota Plant Life. 



145 



localities. One variety, the river-moss, is a common aqtiatic 

 plant in Minnesota, forming slender tufts of delicate leafy stems, 

 attached to pebbles and rocks, on river-bottoms, in rapids or in 

 pools. Besides this particular species of aquatic moss, there 

 are a number of others which have the same habitat. 



Peat-mosses. The peat-mosses belong to the lowest family 

 and are in some instances aquatic. They are familiar objects 

 in the tamarack swamps of Minnesota, where, if undisturbed, 

 they may produce hemispherical patches usually of a gray 



Fig. 46. Road across a peat-bog; tamaracks and birches in background. Near Grand Rapids, 

 After photograph by Mr. Warren Pendergast. 



color but often shaded with a purple, yellow or red, and rarely 

 of a bright grass-green. They are peculiar for their power 

 of absorbing water, and this they do by means of special 

 water-reservoir cells which are mingled with the green cells of 

 the leaves. Indeed the water-reservoir cells form the principal 

 bulk of a peat-moss leaf, while the starch-making cells are dis- 

 posed over them or between them in a delicate green network. 

 The stems and branches, too, are covered with layers of such 

 reservoir-cells so that if a tuft of peat-moss is wrung in the hands 

 water can almost always be squeezed out as from a sponge. 

 II 



