134 VIVIPAEY [CH. VIII 



moist situations. The flowers, or even entire spikelets, 

 grow out into minute leafy buds, with rudimentary roots 

 at the base, and fall ofif like the bulbils of other mono- 

 cotyledons, taking root directly in the damp soil. The 

 phenomenon must be looked upon as a case of apogamy, 

 since the development of sexual organs is entirely passed 

 over ; the parts which would normally have become ovary 

 and stanaens being transformed into leaves. In some 

 species or varieties — e.g. Poa alpina, Festuca ovina — this 

 viviparous condition may coexist with normal flowers and 

 spikelets ; in others — e.g. Poa lama, var. stricta — only the 

 viviparous state occurs. 



In the following arrangement the student should note 

 that the terms " Seed " and " Fruit " are used in the 

 ordinary sense of the farmer and seedsman: by the 

 former is meant the " seed " as it comes in samples into 

 the market, when the true fruit or grain (Caryopsis) is 

 almost invariably invested by adherent "chaff" — i.e. 

 palese or glumes or both. When the word Caryopsis is 

 employed, I mean it strictly in the botanical sense ex- 

 plained above. In Hordeum, for example, we never see 

 the true fruit, the grain consisting of the caryopsis with 

 paleas so closely adherent to it, that we are apt to take 

 them as part of the grain itself The true seed, in the 

 strict botanical sense, is never seen as a naturally separate 

 organ in our native grasses ; and, as already explained, 

 only very few exotic grasses ever shed it — e.g. Sporobolus. 



