310 Fortieth Annual Meeting 



centage of the normal price. It is suggested, therefore, that 

 pearl experts would do well to give the actual Japanese 

 methods their careful attention. 



[Since the meeting of the Fisheries Society word has 

 come from the Science College in Tokyo that extensive ex- 

 priments are under way to improve the process above noted. 

 The process is still a secret one, and no one but the actual 

 operators know the way in which the artificial cores are 

 inserted between the shell and the mantle of the oyster. 

 From the tenor of the letter one infers that the pearls of 

 these experiments have not up to the present time been 

 large enough to "spoil the market." It would be of great 

 interest to obtain details at the Japanese end of the line.] 



DISCUSSION 



Dr. W. p. Herrick, New York City : This matter of the mechanical 

 production of round, perfect pearls is of a great deal of interest to me, 

 because for nineteen years it has been my wish to make experiments in 

 that Hne. It was only this summer that the opportunity came, however, 

 on the 10th of July, when I commenced some work of that nature. I 

 used two varieties of mussel, the soft-shell clam, and the oyster, and 

 then worked on the various Unios ; and afterwards I got some of the 

 western varieties through the kindness of Dr. Coker. Now this matter 

 has come up so quickly that there is little more to show you than a 

 few specimens. As I understand it, these are the first experiments of 

 the kind that have been undertaken in America, and the first on 

 American Unios. I think it might be interesting to exhibit the speci- 

 mens so far obtained from the experiments. 



Perhaps, by way of explanation, it might be well to add that it is now 

 generally admitted that an epithelial cyst is essential to the formation of 

 a round pearl. It also might be interesting to add that Dr. Hornell, in 

 speaking of cysts in this regard, says that these cysts though small are 

 usually visible to the eye and measure 1.3 mm. in diameter; he after- 

 wards says that some are about half that diameter. That would be 

 about a thirtieth to a sixtieth of an inch. Dr. Jameson, in speaking of 

 the mussel cysts producing pearls, says that they are about a millimeter 

 in diameter and of a yellowish color. So just in explanation of the 

 specimens I was going to submit I make this statement. 



I will say that Professor Nishikawa's investigations are wonderful. 

 I have not seen a pearl ; from a press notice, however, it appears that 

 a good many of those pearls had a black spot, but that he has produced 

 a perfect, spherical pearl. 



I would like to say (exhibiting specimen to Society) that this speci- 

 men from a Unio shows a little yellowish-brown cyst about half the 



