The Queensland Naturalist, 
March, 1935. 
58 
— a bulb. The roots of epiphytic Orchids serve not 
only as a means of obtaining nourishment, but a means of 
attachment. In some cases they contain chlorophyll, the 
green colouring matter of plants, and probably perform 
in part the functions of leaves. The roots of most epip- 
hytic Orchids are enclosed in a spongy sheath termed the 
velamen (Latin meaning a covering). It is the velamen 
which gives the white corky appearance to Orchid roots, 
especially when dried. It is a many-layered, spongy 
tissue whose function is to suck up rapidly and afterwards 
hold moisture, to be drawn upon by the plant as required. 
In some extreme cases such as two peculiar subterranean 
Orchids, one of which was recently found in Western Aus- 
tralia the other in New South Wales, roots may be entirely 
absent. The leaves are extremly variable, sometimes be- 
ing totally absent and only represented by a few scales 
on the flowering stem as in the common Dipodium pane- 
tatum, the Spotted or Hyacinth Orchid. In one case, 
Taeniophyllum, there are no leaves of any sort, not even 
scale leaves, and in this case the roots are green coloured 
and probably perform in part the functions of leaves, the 
green colouring matter or chlorophyll absorbing certain of 
the rays of light whose energy is used to build up simple 
carbohydrates like starch and sugar, or perhaps primar- 
ily proteins. The flowers are variously arranged, they 
may be solitary or in pairs in the leaf axils, in racemes or 
spikes, in heads or in branched panicles. 
The floral structure has already been mentioned in a 
general way. The stamen is generally regarded as being 
represented in all cases of Australian Orchids by a single 
fertile anther, borne at the top of the column. The pollen 
is mostly somewhat waxy and is usually arranged in two 
to eight small globose, egg-shaped or club-shaped pollinia 
or pollen masses, which are either free or attached by a 
strap-like body called the caudicle to an adhesive gland 
or disc on the rostellum. The stamens are one or two, 
just below the anther. The upper border is usually 
though not always, developed into a small body called 
the rostellum, a hinged or easily detachable organ supposed 
to represent a sterile or abortive stigma. The column i$ 
variously shaped, lobed or winged, it may or may not be 
developed into a foot at the base, and has an important 
place in Orchid classification. The ovary is inferior, that, 
is below the perianth segments and stamens, which are 
situated above it. The ovary eventually develops into a 
seed sapsule, the seeds themselves being minute and borne 
in great abundance. 
Various schemes of classification of Orchids have been 
proposed. In Bailey’s “ Queensland Flora,” the only 
