5 
by the use of coir dust as a medium in which to plant the newly transferred 
small seedlings. Coir dust is light and holds a great deal of moisture without 
becoming sodden; it therefore maintains the constant moist conditions which 
the orchid seedlings need, and at the same time is well aerated. Furthermore, 
it is free from moulds, and rots very slowly. The pots of all small seedlings 
also are plunged into a deep bed of coir dust, which maintains a cool humid 
atmosphere all around; for this purpose it is probably better than a free water 
surface. 
The kinds of orchids most useful for the lowlands of Malaya are the scorpion 
orchids (Arachnis), the Vandas (especially terete Vandas), the red-flowered 
Renantheras, Dendrobiums of the section Ceratobium from Eastern Malaysia, 
and the Malayan terrestrial genus Spathoglottis. Vanda, Arachnis and 
Renanthera are particularly useful because they are very easy to propagate and 
stand full sun; they may therefore be grown in any garden, only needing a 
supporting post with a good layer of compost around the base. The only 
wild orchid of this alliance which is really strong and free-flowering in Singapore 
is the white scorpion orchid, Arachnis Hookeriana (also called A. alba), but a 
number of hybrids produced from this, and also from terete Vandas, by crossing 
with a variety of related species, have proved very free-flowering. The intention 
is to increase the number of these, and many hundreds of new seedlings are now 
at various stages of development. It is necessary to raise a large number of 
seedlings to secure the maximum possible variation, and so increase the chance 
of producing a few really good novelties. For success, a plant must be strong, 
free-flowering, and have large flowers of good form and distinctive colour, and 
among hybrids of the second and third generation only a small minority may 
have all these desirable features. 
The following free-flowering hybrids have now been produced, and are being 
propagated from cuttings: 
Arachnis Maggie Oei (A. flos-aeris x A. Hookeriana var. luteola) 
Arachnis Ishbel (A. Hookeriana x Maingayi) 
Arachnis Catherine (A. Hookeriana var. luteola x Sulingi) 
Aranda Deborah (A. Hookeriana x V. lamellata) 
Aranda Hilda Galistan (A. Hookeriana x V. suavis) 
Aranda Nancy (A. Hookeriana x V. Dearei) 
Aranda Mei Ling (A. Hookeriana x V. sumatrana) 
Vanda Cooperi var. Cho Yarn Neo (V. Miss Joaquim x Hookeriana) 
Vanda Mine. E. M. E. Dinger, a selected variety (V. Miss Joaquim x tricolor) 
Vanda Amy (V. Hookeriana x tricuspidata) 
Vanda Nam Kee (V. Cooperi x Marguerite Maron) 
Aranthera Mohamed Haniff (Arachnis Hookeriana x Renanthera coccinea). 
Pure white Vanda hybrids have been produced by the use of a white variety of 
V. Hookeriana, but the plants are not strong. A further crossing with a large 
white V. teres has been made. 
Plants of the genus Dendrobium cannot be grown in beds like Vandas, are 
slower to propagate and require more careful handling. The flowers however 
are very beautiful and durable, and the hybrids are mostly stronger and more 
free-flowering in Singapore than their parents. 
Good progress was made in methods of cultivation of Dendrobiums. during 
the year. There is no doubt that, when the plants are properly established 
in pots, intensive manuring may be practised, and that plants so manured will 
attain a much larger size than without such treatment. Intensive manuring 
seems to have no deterrent effect on flowering. In other countries manuring of 
orchids has been considered unnecessary, but it is certainly necessary for best 
results in Malaya. 
u 
