Proceedings of the Linnean Society of London - University Library

LINNBAN SOCIETY OF LONBOX. 29
the number of beds, and can prevent catastrophes from devastating
the oyster-populations, so that the divers can collect the
spoil annually in their tens of millions, we need not fear any
scarcity of pearls.
As Boutau, who thinks favourably of artificial methods, points
out*: "Mais il ne faut pas oublier que r'infectiou d'un animal
par un parasite ne favorise pas precisement le developpement
normal da sujet infeste." He advocates as an alternative method
experimental trepanning of the shell, but that or any other mode
of individual treatment is clearly impracticable in dealing with the
millions of the Ceylon pearl-banks. My own opinion is that,
although all pearl-production is a departure from the normal, the
pearl-inducing parasites are not sufficiently abundant to affect
seriously the health of the oyster ; and that, to reverse the popular
saying, if we attend to the prosperity of the bed as a whole, the
individual oysters may be left to take care of themselves, both in
regard to health and pearl-production.
I quoted last year Linnteus's statement, made in connection with
his process of artificial pearl-formation :— " As all the knacks of
Nature are very simple, so is this when properly hit upon." It
was certainly much simpler t than the " knack of Nature " I have
just discussed, requiring a parasitic worm aud several successive
hosts, which we now believe is necessary to produce the finest
Oriental pearls. And although 1 hope we have now " properly hit
upon " this " knack of Nature," I do not for a moment suppose
that the subject is exhausted. There is still much to be investigated.
Mr. Hornell, another Eellow of our Society, is now
Inspector of Peai'l Banks to the Ceylon Government, and is ably
carrying on the work commenced in the Grulf of Manaar fifty years
ago by our former Fellow, Dr. Kelaart.
Altogether, I think we may feel that the Linnean Society has
played a not unimportant part in the investigation of the connection
between parasites and pearl-formation ; and that therefore,
perhaps, it is not inappropriate that one of your Anniversary
Addresses should have been devoted to that subject.
Mr. Henet Geotes moved :—That the President be thanked
for his excellent Address, and that he be requested to allow it to
be printed and circulated amongst the Pellows—which, after
being seconded by Dr. Maxwell T. Masters, was put and carried
unanimously.
* Arch. Zool. Exper. 1904, p. 89.
t In the sixth edition of the
gives the following deSuition
' System a Naturae' (1746), p. 195, Linnaeus
of a pearl :— '" Calculus testa3 concharum.
Margarita, Unio. Ijocus : Testae exci-escentia latere
latus perforatur
interiore, duiu exterius
"—which is certainly simple enough.