390 THE STORY OF PLANT LIFE 



anthers are erect, entire at the tip, linear, fixed by 

 the base, opening inwards, two-celled with a claw at 

 the tip. The ovary is one-celled, with three or two 

 carpels, in the same or a distinct glume. There is a 

 single style, two to three slender, linear stigmas, 

 papillose all over. The ovule is single, basal, ana- 

 tropus, erect. The fruit is an achene, small, flattened, 

 the style often two-cleft, or three-angled, when three- 

 cleft, enclosed in the perigynium in Carex. The 

 testa does not adhere to the pericarp. The seed is 

 solitary, erect, the testa membranous. The endo- 

 sperm is floury. The embryo is small, at the base of 

 the endosperm. 



The flowers are wind-pollinated. 



No properties of economic importance are afl"orded 

 by the plants of the Sedge group, except that Galin- 

 gale was formerly used medicinally, the cotton of 

 Cotton-grasses has been used for wick or for weaving 

 or stuffing pillows, and Sand Sedge is useful on the 

 coast for binding the sand together. 



Bog-rush (Schcenus nigricans). 



Some of the species of this genus, Schcenus^ have 

 been used as cordage, hence the generic name. The 

 second refers to the black sheaths. The habitat and 

 habit are indicated in the English name. 



Local in its occurrence, and restricted to wet 

 regions, or the west of England and North Britain as a 

 whole, Bog-rush is found from Shetland to Cornwall. 



