750 
THE TROPICAL 
AGEICULTURIST. [May 2, 1904. 
and Ratnapuia Rubber Districts and after 
observing and investigating the disease on 
the Government Plantations, 1 recommended 
to Government that steps should be taken 
to eradicate the disease at these places. 
The lease expired on 29th February last 
and Government having decided to take the 
place into their own hands until freed from 
disease, I went down on March 1st find 
began operations against the canker. This 
work will be carried on until the canker 
is eradicated, considerable progress having 
already been made.— I am, &c. 
(Signed) J B Carruthers. 
Govt. Mycologist and Asst. Director, R. B. G. 
MR. . STAEEY IN JAVA. 
VISITING THE WANGIE WATTIB ESTATES. 
In a letter to a Ceylon shareholder dated 
March 19th, Mr. R N G Bingley. Managing 
Director of the Wangie Wattie Planting Co., 
says he was expecting Mr. Starey at Iji 
Wangie that day for a few days,' visit on 
his way back from bis East Java Coffee 
Estates. Mr, R C ^Yright, the well-known 
Ceylon planter, repoi ted on the estates of the 
Company on January 25th this year, having 
last visited them four years ago, and states 
that the general all round improvement made 
between those dates is simply wonderful, 
not only in the condition of the tea bushes 
but also in the all-round cultivation of the 
estate. A yield of from 800 to 1,000 lb. per bouw 
can be looked forward to with confidence, 
costing 20 cts. per lb. 
VANILLA VS. AETIFICIAL VANILLIN. 
MEMORANDUM FROM THE IMPERIAL 
INSTITUTE. 
The following letter and a memorandum 
was laid on the Press Table at the Colombo 
Secretariat : — 
Board of Trade, Commercial Department 
No. 7, Whitehall Gardens, London, S.W., 
January 2nd, 1904. 
Sir,— I am directed by the Board of Trade 
to acknowledge the receipt of your letter of 
the first ultimo asking for information with 
regard to Vanillin. In reply, I am to trans- 
mit to you herewith copy of a memorandum 
on the subject which has been prepared at 
the Imperial Institute at South Kensington. 
I am to suggest for Mr. Secretary Lyttle- 
ton's consideration that it might be advisable 
to send copies of this memorandum to 
Mauritius and any other Colonies which are 
largely interested in Vanilla, as well as the 
Seychelles.— I have the honour, &c., 
(Signed) H. Llewelyn Smith. 
The Under Secretary of State, Colonial 
Office. 
The memorandum gives an exhaustive 
account of the discovery in 1858 by Gobley 
and the subsequent investigations into 4 
artificial preparations of Vanillin which is 
the constituent to which vanilla owes its 
aroma and flavour. It states that in November 
last good qualities of vanilla were saleable 
at 17s. to I9s. 6d. per lb. while the price of 
the artificial substitute. Vanillin, has fallen 
from £9 in 1890 per lb. to £l Is. 4d. in 
November last. A stateqaent is given of the 
imports of vanilla into the United States of 
America showing that in 1894 the figures 
were 171,556 lb. valued at §727,853, at an 
average per lb. of $4 2c,. and in 1902 the 
figures were 861,739 lb. valued at $859,399 at an 
average cf $2. 3c— indicatinar that "although 
there has been no falling off in the demand 
for vanilla there has been a great decline in 
value. In London the prices obtained in 
February ranged from 22s. 6d. to i4s. 6d. per 
lb. short chocolate coloured beans and 7s. 6d. 
to lis. 6d. per lb. "foxy brown" beans. In 
conclusion. Professor Wyndham R Dunstan 
of the Imperial Institute, who has drawn 
up the above memorandum, says "it is not 
possible to encourage proposals to prevent 
the sale of Vanillin as > ' substitute ' for 
vanilla." 
» 
CEYLON PEAEL OYSTEE FISHEEIES. 
PEOFESSOR HERD MANS REPORT. 
The following is the remainder of the report by 
Professor Heidnian (as summarised by him) on tl e 
Pearl Oyster Fisheries of the Gulf of Mannar, cf 
which the first and last portions were quoted in 
last monih's T. A.: — 
Turning to the pearl-tofmation which is an 
unhealtliy or abnormal proces?, we find that in the 
Ceylon oyster there are several distinct causes 
which lead to the production of pearls. Some pearls 
or pearly excrescences on the interior of the shell 
are due to the irritation caused by boring sponges 
and burrowing worms. Minute grains of sand and 
other foreign particles gaining access to the tody 
inside the shell, which are popularly supposed to 
form the nuclei of pearls, only do so, in our 
experience, under exceptional circumstances, la 
the whole of our obfervations we have only record-s 
of three cases in which a grain of sand undoubt- 
edly formed the nucleus of a pearl. Pearls of 
another class are found in the muscular tissue of the 
animal, most frequently in the levators, in thepalpar 
region, and in the paliial insertions. These muscle 
pearls have no foreign bodies as nuclei. They form 
around minute calcareous concretions — the colcos- 
pherules — which are sometimes very abundant in 
the tissues. The best pearls, however, the "fine" 
or "Orient" pearls, lie in the paliial connective 
tissue at the sides of the body or in the tissues 
around tha liver and kidney, or, when large, they 
may be free in any cavity of the body. The 
majority of these line pearls contain as their nuclei 
the more or less easily recognisable remains of 
certain Platyhelminthian parasites, 'which we 
identify as the larval condition of a Cestode be- 
longing to the genus Tetrarhynchus, probably 
new to Science. We propose to describe it under 
the name Tetrarhynchus unionifacior, in allusion 
to its connection with pearl * formation. We, 
have traced most stages in the life history of this 
pearbproducing Tetrarhynchus, and find that it 
passes from the body of the pearl-oyster into that 
of the file-fishes {Balistes mitis and B Stellai-us), 
which certainly eat oysters, and from these intp 
some larger animal— possibly the large Trygon or 
Kay— which preys upon the file fishes. The adult 
parasitic worm in its last host must then set free 
its numerous young embryos. These we have found 
in the sea, and also enclosed in small cysts iu the 
* Uoio was used by classical writers for the best of 
oriental pearh, 
