Tan. 4442, 
PESOMERIA tTetracona. 
Square-stalked Pesomeria. 
Nat. Ord. Orncurpacex®.—GYNANDRIA MonaNDRIA. 
Gen. Char. Sepala subsequalia libera, sponte decidua. Petala conformia, basi 
column adnata, persistentia. Labellwm posticum, cum columna connatum, 
basi gibbosum, limbo indiviso convoluto. Columna clavata semiteres, clinandrio 
dentato. Pollinia 4 cuneata.—Herba terrestris; caule tetragono, foliis mem- 
branaceis plicatis, racemo laterali simplici, bracteis sponte secedentibus ; radicibus ~ 
crassis simplicibus fibrosis. Lindl. — 
PEsoMERIA fetragona. 
Prsomerta tetragona. Lindl. in Bot. Reg. Misc. 1838, n. 6. 
EpIpENDRUM tetragonum. Thouars, Orchid. Afr. t. 33, 34. 
A very remarkable Orchideous plant, native of the Isle of 
Bourbon, introduced to our stoves by the Messrs. Loddiges, but 
first detected and described, as an Zpidendrum, by M. Aubert 
du Petit Thouars. Dr. Lindley has rightly determined it to be a 
very distinct genus, to which he has given the name of Pesomeria, 
from currw, to fall off, and pepos, a part; in allusion to the 
sudden falling off of the convolute bracteas, of the sepals and 
petals also, leaving the labellum (which is decurrent with the 
base of the column), as shown in the two lower flowers in the 
spike of our figure. Dr. Lindley observes that the genus differs 
from Bletia in its four, not eight, pollen-masses; but in our 
plant each pollen-mass is two-lobed, as if of two combined. 
Descr. Stem afoot or more high, erect, jointed, about as 
thick as the human finger, sharply four-angled and almost 
winged at the angles. Leaves inserted at the articulations, 
ovato-lanceolate, striated and somewhat plaited, membranous, - 
much acuminated. Peduacle arising from the inner base of a 
lateral leaf, a foot high, bracteated. Flowers rather large, eight 
to ten ina lax spike. Floral bracteas sheathing, deciduous. 
Sepals and petals uniform, spreading, oblong, acute, greenish 
_ externally, within red-brown, tinged with green. Lip applied 
close to the column, the base decurrent with it, the side lobes 
MAY Ist, 1849. : 
