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FRE ORGHID: REVIEMA 
VoL. XVIII.] OCTOBER, toto. [No. 214. 
THE EVOLUTION OF THE ORCHIDACE, 
(Continued from page 166). 
THERE now remains the large tribe Vandez to be considered, in which the 
culminating point of development in the Orchidacee is reached. It is a 
vast and polymorphic tribe, and contains such diverse genera as Cymbidium, 
Zygopetalum, Lycaste, Stanhopea, Catasetum, Cycnoches, Maxillaria, 
Odontoglossum, Oncidium, Vanda, Phalenopsis, Angrecum, and 
numerous other popular garden genera. Bentham, in 1881, estimated that 
it comprised 130 genera and about 1,400 species, and the number has been 
considerably augmented since then. He assigned to the tribe much the 
same limits as did Lindley, and remarked of it as follows :— 
‘The plants are mostly epiphytical and frequently pseudobulbous. The 
inflorescence is generally lateral, although in a few genera it terminates 
leafy stems. The essential character resides in the anther and pollinary 
apparatus. The anther, operculate and deciduous as in Epidendrez, is 
more closely incumbent on the rostellum, and when mature usually appears 
one-celled, or nearly so; the two cells, perhaps always distinct in the young 
bud, become confluent when open, or are only separated by a partially 
raised line in the anther case, and in all probability are always divaricate, 
not parallel as in Epidendree. The pollen of each cell is a waxy, globular, 
ovoid, or oblong mass, not tapering to a point or caudicle, and either entire 
or more or less divided into two by a transverse or oblique furrow or section. 
Thus the pollen-masses, when four in the anther, are fore and aft in each 
pair, not all four collateral and parallel, as in most Epidendree. When 
the flower opens, the anther-case is very readily detached, leaving the two 
pollen-masses or pairs of pollen-masses belonging to the two cells separately 
and firmly attached toa scale or plate which becomes detached from the 
back of the rostellum. This scale or plate, with the attached pollen-masses, 
constitutes the pollinarium. When it is small and thick, and almost wholly 
viscid, it assumes the appearance of a gland, and is so denominated ; but in 
many cases it takes the shape of a broad scale, or is prolonged into a linear 
or oblong, single or sometimes double, stipes, bearing the pollen-masses at 
the further end; but the under surface at the lower end is always highly 
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