Chap. VIH. LEEESIA. 333 



genus Hordevm it has been shown by Delpino* that 

 the majority of the flowers are cleistogamic, some of 

 the others expanding and apparently allowing of 

 cross-fertilisation. I hear from Fritz Muller that 

 there is a grass in Southern Brazil, in which the 

 sheath of the uppermost leaf, half a metre in length, 

 envelopes the whole panicle; and this sheath never 

 opens until the self-fertilised seeds are ripe. On the 

 roadside some plants had been cut down, whilst the 

 cleistogamic panicles were developing, and these 

 plants afterwards produced free or unenclosed panicles 

 iof small size, bearing perfect flowers. 



Leersia oryzoides. — It has long been known that 

 this plant produces cleistogamic flowers, but these were 

 .first described with care by M. Duval-Jouve.f I pro- 

 cured plants from a stream near Eeigate, and cultivated 

 , them for several years in my green-house. The cleis- 

 .itogamic flowers ar« very small, and usually mature 

 -their seeds within the sheaths of the leaves. These 

 flowers are said by Duval- Jouve to be filled by slightly 

 viscid fluid; but this was not the case with several 

 that I opened; but there was a thin film of fluid 

 between the coats of the glumes, and when these were 

 pressed the fluid moved about, giving a singularly 

 deceptive appearance of the whole inside of the flower 

 being thus filled. The stigma is very small and the 

 filaments extremely short ; the anthers are less than 

 •^Q of an inch in length, or about one-third of the 

 length of those in the perfect flowers. One of the 

 three anthers dehisces before the two others. Can 

 this have any relation with the fact that in some other 



* ' BoUettini del Comizio agra- on Hordeum, in ' Monatsberieht d. 



■rio Parmense.' Marzo e Aprile, K.Akad. Berlin,' Oct. 1872, p. 760. 



1871. An abstract of this valuable t 'Bull. Bot. Soc. de France.' 



paper is given in ' Bot. Zeitung,' torn. x. 1863, p. 194. 

 1871, p. 537. See also Hildebrand 



