Ludwigia octovalvis 水丁香 _ Hygrophila pogonocalyx 大安水蓑衣 _ Titanotrichum oldhamii 俄氏草 _ Taiwan postage stamps 0 3 n o v.2 O O 6

Ludwigia octovalvis (Jacq.) P.H.Raven 1 9 6 2
Hygrophila pogonocalyx Hayata 1 9 2 0
Titanotrichum oldhamii Soler. 1 9 0 9

the latter two are endemic to T a i w a n.

Ludwigia was named by Carolus Linnaeus after Christian Gottlieb Ludwig ( 30 Apr. 1709- 7 May 1773), professor of Medicine Leipzig and botanical author, who was apparently not amused by this honour.

Hygrophila is one of only two genera in its family Acanthaceae that contains aquatic plants, the other being Justicia.