LINNBAN SOCIETY OF LONBOX. 29 



the number of beds, and can prevent catastrophes from devas- 

 tating 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 investi- 

 gated. 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 con- 

 nection between parasites and pearl-formation ; and that there- 

 fore, 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 ' System a Naturae' (1746), p. 195, Linnaeus 

 gives the following deSuition of a pearl : — '" Calculus testa3 concharum. 

 Margarita, Unio. Ijocus : Testae exci-escentia latere interiore, duiu exterius 

 latus perforatur " — which is certainly simple enough. 



