PEARLS.—MOTHER OF PEARL. 65 
early Spanish settlers gave, and is of doubtful 
meaning. . 
“Shells of this family have their center of 
distribution in Australian and adjacent seas. 
Quantities abound upon the coast of Japan, 
where they are known as ‘ Awadi.’ Other 
names by which they are often called are ear- 
shell, green ear, Omer shell, ete. 
“ Haliotis splendens and 1. tuberculata are 
the names science has given to the beauties 
you have in your hands, Tom. 
“ An enormous traffic is carried on in these 
shells so useful in delicate inlaying, in lacquer, 
and other ornamental work. The animals in- 
habiting these palaces are considerably sought 
after for food, while fine pearls have been 
found within the mantle of some. The irides- 
cent tints of these shells are produced by the 
fluid secretion with which the interior of the 
shells are lined; this hardens quickly and be- 
comes nacre, presenting a beautifully smooth 
and polished surface to the tender body of the 
animal within. They are also due to the ex- 
cessively thin laminations, irregularly overlap- 
ping, laid on in delicate semitransparent films. 
The thinner the laminations of this nacre mem- 
brane the more transparent, and hence the 
more lustrous and beautiful, the shell. 
