92 American Fisheries Society 



linear dimensions, the same sex, and all marks indicating 

 them to be of the same age, the advantage of weight was 

 with the artificially reared shell. This is a limited com- 

 parison, but as neither of the shells was selected, it is 

 good so far as it goes. The thriving condition of the 

 mussels is an index of the value of the method. I know of 

 no other plan yet devised that gives as favorable results. 

 For experimental purposes, pearl culture, or for even the 

 commercial production of mother-of-pearl, the method 

 seems to offer exceptional possibilities. 



