PEARL-FISHING IN CEYLON. 313 
are assembled on the coast, busily employed in protecting the 
divers by their incantations against the voracity of the sharks. 
These are the great terror of the divers, but they have such 
confidence in the skill or power of their conjurors that they 
neglect every other means of defence. The divers are paid in 
money, or receive a part of the oyster-shells in payment. Often, 
indeed, they try to add to their gains by swallowing here or there 
a pearl, but the sly merchant knows how to find the stolen 
property. The oysters, when safely landed, are piled up on mats, 
in places fenced round for the purpose. As soon as the animals 
are dead, the pearls can easily be sought for and extracted from 
the gaping shells. After the harvest has been gathered, the 
largest, thickest, and finest shells, which furnish mother-of-pearl, 
are sorted, and the remaining heap is left to pollute the air. 
Some poor Indians, however, often remain for weeks on the spot, 
stirring the putrid mass in the hopes of gleaning some forgotten 
pearls from the heap of rottenness. The pearls are drilled and 
stringed in Ceylon, a work which is performed with admirable 
dexterity and quickness. For cleaning, rounding, and polishing 
them, a powder of ground pearls is made use of. 
The Pacifie also furnishes these costly ornaments to wealth 
and beauty, but the pearls of California and Tahiti are less 
prized than those of the Indian Ocean. 
Pearl-like excrescences likewise form on the inner surface of 
our oysters and mussels, and originate in the same manner as 
the true pearls. The formation of the pearl, however, is not 
yet quite satisfactorily accounted for. Some naturalists believe 
that the animal accumulates the pearl-like substance to give 
the shell a greater thickness and solidity in the places where it | 
has been perforated by some annelide or gasteropod; and ac- — 
cording to Mr. Philippi, an intestinal worm stimulates the exu- 
dation of the pearl-iike mass, which, on hardening, encloses and 
renders it harmless. 
Brillianey, size, and perfect regularity of form are the 
essential qualities of a beautiful pearl. Their union in a single 
specimen is rare, but it is of course still more difficult to find a 
number of pearls of equal size and beauty for a costly necklace 
or a princely tiara. 
Nature has given the bivalves the same beauty of colouring 
