5 
It was found that in flasks plugged with cotton wool which had been 
disinfected with picric acid and mercuric chloride, germination was poor and 
that seedlings transplanted into flasks so plugged tended to turn yellow. It 
seems possible that the mercuric chloride poisons the culture medium and 
although these plugs gave almost entire protection against fungus infection, 
their use has been abandoned. 
Mr. Pestana carried out a series of experiments with small seedlings in 
pots to ascertain their reaction to feeding with artificial manures. The seed¬ 
lings were between 1 cm. and 8 cm. tall, each set and its controls being uni¬ 
form in size. They were given weekly application of a mixture supplying 
nitrogen, phosphorous and potassium, the controls receiving water only. In 
most cases there was a spectacular increase in height of the seedlings, this 
being the only dimension measured. The monopodial orchids, such as Vanda 
and Aranda naturally showed a larger increase than the sympodial ones such 
as Dendrobium, but inspection of the latter showed that there had been a 
considerable increase in overall size. 
Experiments in a modified method of making beds for such orchids as 
Vanda, Aranda, etc. have been begun. The usual mixture of half rotted com¬ 
post and cattle manure is very effective but it breaks down so rapidly that 
constant renewing and replanting of the beds is necessary. Beds have now 
been made substituting burnt earth, either newly made, or that discarded 
from pot plants, for the compost, and these promise well, for the mixture 
provides the open texture needed for the feeding roots of the orchids and pre¬ 
serves this texture for a much longer time than the compost. 
The hybrid Vanda Tan Chay Yan, which was mentioned in last year’s 
report, has fulfilled the promise given by the flowering of the first seedling. 
It is no exaggeration to say that it is the finest Vanda hybrid yet raised in 
Singapore and we venture to assert that it will hold its own with any Vanda 
hybrid from any part of the orchid, world. All the seedlings seem to be hardy 
and free flowering and remarkably uniform in vegetative form and flower 
colour. They will grow vigorously in burnt earth beds. 
New hybrids which flowered for the first time during the year are Den¬ 
drobium Gracia Lewis x D.Phalasnopsis, which gives promise of being an 
excellent cross; Dendrobium Ursula x D.undulatum; Vandanthe Ellen Noa 
x Arachnis Maggie Oei; Vandopsis lissochiloides x Arachnis Maggie Oei; 
and Arachnis Hookeriana x Aerides odoratum. 
A plant of a new Spathoglottis raised by Messrs. A. de Souza and W. 
de Silva was presented to the Gardens by the growers. It is a cross between 
Spathoglottis Primson and S.plicata and it is a vigorous plant with a large 
head of finely coloured flowers. Mr. Lee Kim Hong produced a new hybrid 
between Dendrobium Schulleri and D.Phalaenopsis and gave a plant to the 
Gardens. 
A number of crosses between free flowering Singapore hybrids and 
hybrids involving Euanthe Sanderiana have been made. Euanthe Sanderiana 
is a very fine Philippine orchid, closely related to Vanda. It does not grow 
well in Singapore and rarely flowers, but its hybrids, many of which have 
been made in Hawaii, take kindly as a rule to the Singapore climate. Such 
plants are obtained by exchange. It is hoped that in due course the alliance 
with Singapore hybrids will result in new and spectacular strains. 
The hybrids between Arachnis and Vanda, known as Aranda, are nearly 
always sterile when selfed or crossed with other groups, which puts a stop 
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