430 



BRITISH FLOWERING PLANTS 



species, m our 



Fig. 342. Fig. 343. 



Fig. 342.— Sedge {Garex acuta). Male 

 flower, consisting of three stamens in 

 the axil of a bract, b. 



Fig. 343. — Female flower. The bract 

 subtends a compressed ovary sur- 

 rounded by a sac from which project 

 the two hairy stigmas. 



flora, numbering about sixty species. 

 Mr. Reid records fruits of 

 nine species from pre- 

 glacial and interglacial beds 

 in various parts of the 

 country. 



In some species the 

 male and female florets are 

 on difi'erent plants (C 

 dioica) ; in those which 

 are regarded as most typi- 

 cal there are one or more 

 spikelets, consisting of male 

 flowers above, and one or 

 more of female flowers 

 below ; sometimes, however, the male and female florets 

 are in the same spike, either the male above and the 

 female below, or vice versa. In some species (Fig. 343) 

 there are 2 stigmas, in others 3. The form of the one- 

 seeded fruits or 

 " utricles " also 

 gives good specific 

 characters. 



In some species, 

 as, for instance, in 

 C. paludosa, the 

 stomata are pro- 

 tected by a series of 

 cuticular pegs (Fig. 

 344). These hold the 

 air, thus keeping the 

 stomata clear and 

 dry. Even if the 

 leaf be immersed in 

 like a sheet of silver. 



C. pulicaria. — In this species and in C. pauciflora 

 the fruits are narrow, pointed, and spreading or reflexed, 

 so that they would readily be carried away by any 

 passing animal. 



Fig. 344. — Vertical section through part of a leaf of 

 Carex paludosa ( x 200), showing protection of 

 stomata from moisture by papilla-like outgrowths 

 of the under-surface. 



water it is not wetted, but looks 



