The remarkable organ, which in this genus represents 
the flower, and by Botanists is termed spatha, is a leaf 
under a peculiar form of developement, assuming the co- 
lour, and probably the office, of corolla. It is one of those 
deviations from the usual order of Nature, which assist the 
philosophical Botanist in understanding the origin of simi- 
lar organs which have departed more completely from what 
may be called their primitive forms, and which, with cohe- 
sion of parts and alteration of figure, take on new ap- 
pearances and functions, by which they are so far disguised 
as to be recognized only in the few plants in which their 
transition from one form to another has been, as it were, 
arrested in the middle, and remains incomplete. 
The Spatha of the Arum, which is manifestly a coloured 
leaf, goes far in support of the ingenious theory of M. Du 
Petit Thouars, that all parts of the flower and fruit are 
modifications of leaves, or leaves in an altered form; or, 
to employ his own expression,—“ que la Fleur n'est autre 
** chose que la transformation d'une Feuille et du Bourgeon 
* qui en dépend; que la Feuille donne Calice, Corolle, et 
* Etamine, et que le Bourgeon devient le Fruit produisant 
* la Graine;" and that the bud of a tree and the seed of a 
tree differ chiefly in this, that the former is an “ Embryon 
fixe,” a stationary Embryo, and the latter an “ Embryon 
mobile," or moveable Embryo. The points upon which this 
curious speculation depend for support are, that there are 
no limits between leaves, bracteze, calyx, and corolla; that, 
in double or monstrous flowers, the stamens and ovaries 
become foliaceous; that anthers occasionally secrete ovula; 
that ovaries are known to become polliniferous ; that every 
compound calyx, corolla, or ovary, can be shown to be 
made up of a determinate and relative number of simple 
parts; and, finally, that all these organs. in regular flowers, 
in whichsno abortion or obliteration has occurred, are pro- 
duced about their axis, as the leaves about their stem, in 
a spiral, or, by depression and approximation verticillate, 
manner. 
A stemless plant, 13 foot high. Leaves radical, erect, 
alittle longer than the spathe, quite smooth, a little shining, 
with regular parallel veins setting off at an acute angle 
from the midrib, pedate; their middle lobe hastate, hori- 
zontal; their lateral lobes three-parted, and, as it were, 
stalked: the three segments very erect, flat, rolled toge- 
