CHAP. III.] FLUYIALES. 455 



pica^ or the White Arum, belongs to this order ; 

 as does the fragrant rush, Acorus Calamus. The 

 order Typhacese is included by many botanists 

 in Aroidese ; and indeed, the difference between 

 them consists principally in the Bullrushes 

 having no spathe. 



ORDER CCV FLUVIALES, OR NAIADES THE 



POND-WEED TRIBE. 



Floating plants, of which Aponogeton dista- 

 chyon is by far the most beautiful. This plant, 

 which is a native of the Cape of Good Hope, 

 has oblong, deeply-ribbed leaves on very long 

 footstalks, and the flowers in two-cleft spikes, 

 with snow-white bracts, which are very orna- 

 mental and very fragrant ; each flower consists 

 of from six to twelve stamens, and from two to 

 five carpels. The root is tuberous, and eat- 

 able when roasted. The Duckweed (Lemna), 

 which is sometimes included in this order, ap- 

 pears to consist entirely of a few leaves floating 

 on the water, each of which sends down a root ; 

 and many people believe that it never flowers. 

 If, however, it be watched in the months of 

 June and July, two yellow anthers will be seen 

 peeping out of the side of each leaf ; and if the 

 opening be enlarged, the flower will be found to 

 consist of a kind of bag, open on one side, and 

 containing two stamens, with an ovary furnished 



