SPIRODELA. 
495 
(opening in June) with shorter and broader lobes, bearing the anthers above their middle. Of the only remaining known 
species of this curious genus Seemann gathered on the Sierra Madre of Mexico a staminate specimen, in bud only, 
which is distinguished from all others by its greater thickness and by the long spikes of large verticillate 4-parted 
flowers, mostly 6 in a whorl. It may therefore bear the name A. verticilliflorum.I 
