Chap. VIII. LEEESIA. 333 



sliown by Delpino* that the majority of the flowers are 

 cleistogamic, some of the others expanding and ap- 

 parently allowing of cross-fertilisation. I hear from 

 Fritz Miiller 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 develop- 

 ing, and these plants afterwards produced free or un- 

 enclosed panicles of 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 Keigate, and cultivated 

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

 togamic flowers are 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 

 ^ 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 'Monatsbericlit 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 



