moner species is _R. retusa_, with fine
racemes of blush-white flowers, spotted with purple; and the blue _R.
coelestis_. The cultivation is similar to Aerides.

~Saccolabium.~--The Saccolabiums should be grown in a warm house like
Aerides. _S. bigibbum_ and others of its class are pretty, dwarf
species, with yellowish flowers spotted with purple and having a white
lip.

~Sarcanthus.~--Allied to Saccolabium, and having similar cultural
requirements.

~Sarcochilus.~--The species of Sarcochilus need to be grown in
Sphagnum-moss in the intermediate house.

~Satyrium.~--Terrestrial Orchids chiefly from South Africa, needing
greenhouse treatment. The plants must be kept dry during the resting
period.

~Schomburgkia.~--A strong-growing genus, requiring similar treatment to
Laelias and Cattleyas. The best position for them is a sunny situation in
the intermediate house.

~Scuticaria.~--The Scuticarias are handsome, bulbless species, with long,
terete, pendulous leaves, and showy, yellowish flowers, blotched with
purple. They should be grown on rafts, or in baskets suspended in the
intermediate house.

~Selenipedium.~ _See_ ~Cypripedium~.

~Sobralia.~--The species of Sobralia are strong-growing, terrestrial
Orchids with reed-like stems, requiring abundance of water during the
period of growth. Intermediate house. _S. macrantha_ and its white
variety are best known.

~Sophronitis.~--A dwarf genus, best known by _S. grandiflora_, which has
scarlet flowers, and has been used for crossing with Laelias and
Cattleyas. All the species are cool-house plants, needing cultivation in
pans or baskets suspended from the roof. The hybrids succeed best in the
intermediate house.

~Spathoglottis.~--Terrestrial Orchids of similar growth to Bletia,
requiring a pronounced resting period. Intermediate house. Rest dry.

~Stanhopea.~--A fine genus, with large, pendulous, wax-like flowers of
aromatic odour. They should be grown in baskets in the intermediate
house. Rest rather dry in a cool house or vinery.

~Stauropsis.~--Stauropsis should be grown with Aerides and Vandas. The
genus is best known in gardens by _S. lissochiloides_ (_Vanda
Batemanii_) and _S. gigantea_.

~Stelis.~--The plants in this genus possess similar growth to the dwarf
Pleurothallis, and require the same treatment.

~Stenoglottis.~--_S. fimbriata_ and _S. longifolia_ are South African
terrestrial Orchids, needing similar conditions to Disa.

~Tetramicra~ (_L