35? 
NATURE 
[Jun 6, igr2 
neighbourhood are rich in artistic treasures, and 
the owners of these and many smaller collectors 
are lending their best pictures liberally. The 
Raeburns alone will constitute a large and im- 
portant exhibit, and besides these there will be 
seen fine and little-known examples of Reynolds, 
George Jamieson, Allan Ramsay, and many 
others. 
Garden parties or other entertainments are 
offered by the Earl of Moray at Kinfauns Castle, 
the Earl of Strathmore at Glamis, the Earl of 
Camperdown at Camperdown, and by Lord 
Kinnaird at Rossie Priory. 
Lastly, it may be said that the number of dis- 
tinguished foreign guests promises to be very 
much larger than at any recent meeting of the 
Association. It is, doubtless, in compliment to 
the president of the Association that many 
foreign physiologists have been invited and have 
accepted invitations ; among others the names may 
be mentioned of Profs. Leon Asher, Baglioni, 
Botazzi, Fano, von Frey, Firth, Fleischman, 
Gley, Gottlieb, Hamburger, Paul Heger, Kossel, 
Loewi, Lippmann, Meltzer, Hans Meyer, Gustav 
Mann, and Pekelharing. Among the foreign 
geologists, some of the principal names are those 
of Profs. Charles Barrois, @yen, Reusch, Lugeon, 
and Baron Nopsea. But it is neither possible nor 
necessary to set forth here a longer list of -the 
many eminent scientific men who have accepted 
the local committee’s invitation. 
D’Arcy W. THompson. 
THE CEYLON PEARE FISHERY. 
ART vi. of the Ceylon Marine Biological 
Reports (dated January, 1912) contains the 
announcement that the laboratory, which has been 
maintained by the Ceylon Company of Pearl 
Fishers, has been closed, as the leasing of the 
pearl-banks has not proved a commercial success. 
Mr. T. Southwell, scientific adviser to the com- 
pany, discusses the causes of this failure. He points 
out that the uncertain nature of the pearl-fishery 
has been recognised for several centuries, and that 
periods of barrenness have succeeded years of 
plenty. The banks were leased by the company in 
1905, and there were successful fisheries for pearl- 
oysters in 1906 and 1907, since when no fisheries 
have been held. The banks are reported as being 
at the present time absolutely barren, due to the 
rapaciousness of man and his neglect to leave 
breeding stocks, and due also to the attacks ef 
voracious fish. So thoroughly have the banks 
been depleted, not only of pearl-oysters but of all 
molluses, that during the last two and a half 
years fewer than half a dozen molluscs have been 
obtained, in spite of the efforts of divers and the 
use of the trawl and dredge. 
Mr. Southwell holds that, in order that the pearl- 
fishery may be continuous, it is essential that com- 
pact beds of breeding stocks be isolated and pro- 
tected. Since this was realised, preparations have 
been made to afford the necessary protection to 
sufficient breeding stocks when they become avail- 
NO. 2223, VOL. 89] 
able, but unfortunately the opportunity has not vet 
occurred. Mr. Southwell advocates the formation 
of a Government marine department, the duty of 
which shall be the investigation and enhancing of 
the marine resources of the island. He is con- 
fident that a spat-fall will take place at an early 
date, and, should this occur, only thorough in- 
spection and care and foresight in preserving 
breeding stocks are required in order to make the 
banks perennially productive. It is to be hoped 
that, before this repopulation of the banks occurs, 
the Ceylon marine laboratory will have been re- 
opened, and that naturalists will be at hand to 
carry out the recommendations for the fostering 
of the pearl-fishery which are put forward in this 
report. 
The currents during different seasons of the year 
have been investigated by Mr. Southwell and 
Lieut. Kerkham, who have shown that when the 
south-west monsoon is strong the current sets 
nearly due east from the pearl-banks off Tuticorin 
almost directly across to the Ceylon banks. The 
larvee of the pearl-oyster are free-swimming 
in the surface waters of the sea for the 
first five to seven days of their existence. 
They then develop shells, fall to the bottom, 
and become attached there. The writers of 
the report believe that the distance from the 
Tuticorin to the Ceylon banks—about 85 miles— 
can be traversed by the larvee during the period 
of their pelagic life, but only when the monsoon 
is strong. The Tuticorin banks are important, 
therefore, as being the potential source of spat for 
the Ceylon banks. 
Mr. Southwell has continued the observations 
on the pearl-inducing worm—a larval tape-worm 
(Tetrarhynchus unionifactor). He thinks it prob- 
able that only those larve which die in the tissues, 
and thus set up local irritation, cause the forma- 
tion of pearls. He considers it practically certain 
that the larve pass directly from the pearl- 
oysters to the various elasmobranch fishes which 
devour them (that is, that there is not an inter- 
mediate host), but that certain bony fishes, e.g. 
Balistes and Serranus, are subsidiary or parallel 
hosts. 
NOTES. 
On Wednesday, June 26, his Majesty the King will 
lay the foundation-stone of the National Museum of 
Wales in Cardiff. Jt will be remembered that this 
institution was created by Royal Charter in 1907, Sir 
Alfred Thomas (now Lord Pontypridd) being the first 
president, Lord Mostyn vice-president, and Major- 
General Sir Ivor Herbert treasurer. The preliminary 
steps of constituting the court of governors and the 
council took a considerable time, and it was not 
until the end of 1908 that a director of the museum 
was appointed. Dr. W. E. Hoyle, formerly head of 
the Manchester Museum, was selected for the post, 
and began his duties in March, 1909. The schedule 
of requirements for the proposed building was next 
drawn up, and three assessors, Sir Aston Webb, 
Mr. J. J. Burnet, and Mr. E. T. Hall were appointed, 
