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XXIV. On the production and formation of pearls. By Sir 
Everard Home, Bart. V. P.R. S. 
Read May 11, 1826. 
For the last four years I have been engaged, with the aid 
of Mr. Bauer's microscopical observations, in examining the 
mode of generation of the fresh water muscle and oyster ; 
illustrating the changes that occur by Mr. Bauer’s drawings 
in the same manner as has been done with respect to the egg 
of the pullet, the frog, the earth worm and barnacle. But 
as it will require another season to complete this investiga- 
tion, I am desirous of preceding it with an account of the 
formation of pearls ; the discovery of which was made in the 
early parts of my enquiry into the mode of generation of the 
fresh water muscle. 
I am the more desirous of laying before the Society these 
new facts respecting pearls at this moment, when the public 
mind is directed to the improvement of the pearl fishery, and 
therefore every thing respecting them will be received with 
greater interest than at any other time. 
In examining the organs of generation of the large fresh 
water muscle, I very frequently met with what are called 
seed pearls ; and these were always found in the ovarium, or 
connected with the shell on which the ovarium lay. I at the 
same time accidentally discovered that all oriental pearls 
that are split into two halves have a brilliant cell in the centre ; 
