108 
THE PEARL OYSTER 
tendent of Pearl Fisheries comes on a bank of oysters he 
has to determine their age and therefrom to decide when 
it will he remunerative to fish the bank, and to advertise 
the fishery and make all his arrangements for temporary 
buildings, an extra body of Police guards, divers and boats 
and Superintendents, &c., &c., &c., all well in advance. If he 
fishes the oysters a year too late he may lose tbem all, if a 
year too soon be will realize but small results by reason of 
the pearls being too small to command good prices. There- 
fore much stress has been laid on the age of the oyster, and 
the native divers profess to be experts at telling the age. 
Under normal conditions they doubtless are so, but there 
are circumstances to be taken into consideration which 
they do not allow for. For instance they are wrong 
about their starting point, always having mistaken Avicula 
vexillum for the spat of Avicula fucata. But allowing that 
they have bridged that initial error by a very fair guess, 
then comes the point that they do not allow for indivi- 
dualities of growth, and rapidity of gro'ni;h seems to turn 
with oysters, as we know it does with fish, on the favour- 
ableness of the surroundings. Thus we know that out of 
the same hatching of salmon some will descend to the sea a 
whole year later than their twin brethren. And trout in 
one lake or river run very much larger than in another, and 
even in the same river the best holts yield the best fish. It 
is not unnatural that oysters should follow the same rule. 
Accordingly, we find in clusters of oysters considerable 
variation in size, and yet hardly enough to say they belonged 
to diiSerent spattings, though it was contended before me 
by the divers that of the oysters found on the Tholayiram 
Pdr (bank No. 30) some were one year, some a year and-a- 
half, some two years old. They had doubts, however, in 
their own minds. Seeing that all the oysters in one bed 
would seem to be under more or less approximately similar 
conditions, one would not expect to find tlie variations in 
