6i6 



BOTANY OF THE LIVING PLANT 



put up long flowering shafts, each bearing several spikes of unisexual flowers 

 (Fig. 463). In the species named, one or more of the distal spikes bears only 

 male flowers : the lower lateral spikes bear female flowers. In the axil of each 

 glume-like bract of the male spike is a male flower consisting only of three 

 stamens, with no perianth or gynoecium. In a similar position on the female 

 spikes there are found flask-shaped bodies (perigynia), through the open throat 

 of which at flowering a three-branched stigma projects. The perigynium is 

 a bract enveloping the female flower, which has no perianth, and no androecium, 

 but consists of three, or sometimes two carpels, syncarpous and superior. The 

 ovary is unilocular, the ovule solitary, and the fruit a nut. Here the flower is 

 still more simple than in the Cotton-Grass, for there is no perianth, and as 

 the flowers are unisexual, all that remains are the three stamens in the male, 

 and the three carpels in the female. Pollination is by the wind. A large 

 number of flowers of simple structure are aggregated in the inflorescence : 

 cross-pollination is therefore probable. 



The Sedges are of little value for fodder. Drainage oi the wet ground in 

 which they grow promotes the more valuable Grasses, from which they are 

 distinguished by their solid stems and leaf-divergence of J, while in Grasses 

 it is \ : also by the median position of the embryo in the seed, while in Grasses 

 it is placed laterally. 



Family : Gramineae. Example 1 Common Rye-Grass. 



(11) The Rye-Grass (Lolium perenne, L.) is a common grass of meadows 

 and road-sides ; its variety italicum is often cultivated for fodder. It has 



Fig. 464. 



Inflorescence and flower of Lolium perenne. I. shows part of the main rachis, with 

 one lateral spikelet in the axil of the single glume (gl). II. a single flower with its 

 two paleae (p), pendent stamens, and feathery stigmas {st). III. flower dissected 

 out, showing lodicules (I). IV. the gynoecium. V. floral diagram: g/ = glume; 

 gl' = glume which is wanting in Lolium ; p = paleae ; / = lodicules. 



leafy stolons and ascending flowering shoots, and it is easily recognised 

 amongst common Grasses by their long flattened form. Its flowers open in 



