212 



Minnesota Plant Life. 



Sedges. The sedges are a family of plants closely akin to 

 the grasses and with them constituting the fourth order. They 

 are mostly grass-like in appearance, though some, like the bul- 

 rushes, are singular in aspect owing to their special habitats. 

 As compared with the grasses they present some differences 

 which may be kept in mind and should enable one to distin- 

 guish the two families at a glance. The stems are slender, gen- 

 erally solid, instead of hollow as in almost all the grasses. Very 

 often the sedge stem is triangular or quadrangular, a character 



FIG. 93. Cotton-grasses growing in a bed of peat-moss. Near Grand Rapids. After photo- 

 graph by Mr. Warren Pendergast. 



not at all common among grasses. Some sedges, however, like 

 grasses, have cylindrical stems. The leaves are, when present, 

 altogether grass-like. The flowers resemble those of grasses, 

 except that the number of stamens is rarely more than three. 

 The ovary is one-chambered, develops a single seed and in gen- 

 eral resembles the ovary of the grass. The stigma is often 

 three-cleft but sometimes simple or two-cleft. The fruit is 

 ordinarily a three-cornered nutlet with mealy albumen and minute 

 embryo. 



