VLE 
PEARLS.—MOTHER-OF-PEARL. 
F'ascINATING as was microscopic study, Tom 
lost none of his admiration for the abalones, so 
lustrous and iridescent, while Undine looked 
for seed pearls in every bivalve that came into 
her hands. 
Dr. McLean told them the pearly lining of 
the abalones was called mother-of-pearl, or 
nacre, while true pearls were the product of 
different bivalves, the best “solidified drops 
of dew,” as the Orientals call them—being 
found in the pearl oyster (Avicula margarv- 
tifera). 
“ According to an ancient fable,” continued 
the doctor, “oysters rose to the surface of the 
water, opened their shells, and received the 
drops of dew which were speedily transformed 
to ‘white pearls rounde.’ In recognition of 
this fable Thomas Moore wrote: 
‘Precious their tears as rain from the sky 
That turns into pearls as it falls in the sea. 
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