Fer. 1, 1901.] 
THE TROPICAL AGRICULTURIST. 
547 
3. The pearl oyster of the Ceylon fishery, 
almost valueless for its shell, but iislied for its 
pearls. Marketable pearls are found also in the 
two pearl-shell oysters. They are, however, seldom 
as lustrous as those of the true pearl oyster, and 
indeed are merely a bye-product, the shell being 
the chief thing. 
The value of the shell varies considerably, 
good shell of the first or true shell species fetch- 
ing about £100 per ton. This is a lairly constant 
price, as the demand tor white buttons scarcely 
alters. At present the bUick lipped species is 
worth rather more, as fashion now demands a 
button of a mixed colour. Its average price is 
perhaps £80 per ton. The true pearl oyster of the 
Ceylon banks is worth from £2 to £5 a ton for 
its shell, but the market is very small. The 
value of the oyster banks depends on the value of 
the pearls obtained, and while varying with the 
market must always be very much greater than 
that of either of tbe shell .species. This resultis 
very largely due to the fact that the pearl oyster 
is a social bea t, i.e- that thousands and even 
millions attach themselves to a single reef, while 
the two pearl-sliell oysters are found scattered here 
and there, never, except formerly in a few areas 
of Torres Straits, in any very great quantity on 
any single area. It would be obvious however 
that the cultivation of either of the above three 
species would be, even if but very i)artially suc- 
cessful, extremely profitable, and from my ex- 
periences elsewhere, there would seem to be no 
good veason why it sliould not be quite success- 
ful on Ceylon reefs. I have indeed seen very 
many reefs round the coast of Ceylon, apparently 
absolutely identical in their physical conditions 
with reefs in the Pacific Ocean, and in the Maldive 
Group on wnich the black-lipped pearl shell 
abounds. Many quite protected shoals also to the 
north, east and south of Ceylon, appear to nie 
eminently suitable lor the growth of the true pearl 
oyster. 
In Ceylon I had the pleasure on several occa- 
sions of discussing the matter with Capt. Donnan. 
My experience agrees with his as to the immense 
importance of the currents of any area. Indeed, 
in Considering the fauna of any single reef in refer- 
ence to neighbouring ones, the physical conditions 
are the most important factois to be taken into 
consideration. 1. would suggest, then, that the first 
thing to be done is to have made a thorough 
survey for 12, 24 or even 36 months, if necessary, 
of the physical conditions of the reefs in the 
Gulf of Mannar by a competent, practical and, 
if possible, experienced zoologist. The life history 
of the oyster can then be thoroughly worked out. 
The eHects of currents, silt, etc., will be known 
as also the physical conditions of the reefs. 
Suitable reefs in more protected situations could 
then be searched for round the coast of Ceylon. 
On these, cultivation on a large scale could be 
tried, and I have little doubt would be successful. 
Further the reefs and waters of Ceylon have im- 
mense possibilities for the cultivation of the two 
pearl-shell oysters. Great areas are exceptionally 
favourable tor sponge planting, an industry, as 
experiments in the Adriatic have shown, not 
attended with any great dithculties. 
Capt. Donnan has immense, long-continued and 
unique experience of the pearl industry of Ceylon. 
Should there be any intention to appoint a 
scientific man to the work, it should be done 
without delay, so that he may have the benefit 
of Capt, Donnan's knowledge to the very fullest 
extent. He should, too, be in close relation to 
the museum, as he would doubtless require to 
refer to it constantly for literature and special 
information as to the fauna. 
I may take this opportunity to thank all, with 
whom 1 came into contact in Ceylon, for their 
courtesy, kindliness and sympathy.— I am, sir, 
yours obediently, 
J. STANLEY GARDINER. 
Cambridge University, Dec. 16. 
^ 
RUBBER IN FAST AFRICA. 
Mr. Marsden, the British Vice Consulfor the East 
African Protectorate, in his report on the]' trade of 
the country, again emphasises his conviction, pre- 
viously expressed that there is money for the pri- 
vate individual and for the Government it the rubber 
indaatry in the Protectorate were more systema- 
tically worked. "Rubber," he says, "shows an 
advance of 40 per cent on the previous year, but ii 
still far below what it should be and what the 
country is capable of produciog. This is due in a 
Urge measure, to this industry being left to take 
oare of itself, and no properly discinlined or organ- 
ised effort mude to assist it. In times of drought 
and bad harvests the natives fall back on the rubber- 
collecting industry to keep themselves from itarva- 
tion, but in times of plenty the industry is more or 
less neglecterl, andjonly vines which grow in those pla 
ces easiest of approach are tapped, and in many case' 
ruined by being cut to the ground instead of tapped! 
It is somewhat surprising that the attention c- 
planters has not been previously drawn to the aja 
tematic ^cultivation of the rubber vines. ThrouKh 
out the ^territory tbe;soil is sufficiently rich to grow 
rubber vines in perfection without artificial aid, the 
only requisite being water, and on the banks of th« 
Tana and Sabaki rirers that can be obtained all the ' 
year round. With irrigation and under proper ma. 
nagemeut the results should be as satisfactory ag 
ooEeegro\ring."—]ndia-]ubber Trades' Journal, Nov. 36 
INDIA-RUBBER PROPAGATION. 
Colonel A, Bloomfield, writing to the Pioneer 
(Dec. 20) about the propagation of the India-rubber 
tree, remarks that the simplest method of propaga- 
tion is to strike cuttings made of a leaf of the tree 
cut off with about an inch of the twig above 
and below. Every leaf will strike readily. All 
the piece of twig must be underground. 
Our Tka Exports.— A Calcutta merchant 
in a private letter to the Editor of the 
Tropical Agriculttirist, writes:— "I have 
been indebted during the past two years to 
your annual supplenfient for the figures 
giving the Monthly Exports of Tea to Great 
Britain and elsewhere. These cannot, how- 
ever, be tabulated during the course of the ' 
year owing to the way in which the export 
statistics are published vis : to week ends 
instead of for the calendar month. I feel 
sure that, were the export statistics published 
in some such form as annexed, they would be 
of added interest and value to many who 
like myself try to follow the development of 
our Indian and Ceylon Tea Trade ; and I tv^^ t 
it may be possible for you to give them 
the suggested form."— We referred this letter 
to a member of the Chamber's Committee and 
we are glad to learn that it has been agreed 
to adopt the suggestion for the present [ 
year. 
