has experimented with Roentgen rays for that purpose.
As
the fish is enormously prolific it is more probable however that effort
will be directed, instead toward the preservation of the mollusk from
the enemies and accidents which are occasionally greater than its
productiveness.
One
of the greatest dangers in Indian waters to a bed of young oysters is a
little mollusk known locally in Ceylon as suran (Modiola). These
cluster in masses on the sea bottom and spreading over the surface of
the coral, crowd out the delicate young of oysters recently deposited.
The
Japanese fisheries suffer from the occasional infection of the waters
by a weed, dinoflagellata gonyaulax. It accumulates in immense
quantities, causing a wide discoloration of the sea water and is very
destructive to an oyster-bed. It is called the red current or red tide.
So far no preventive or remedy has been found.
Hitherto
the most general and fatal danger to oyster-beds has been the
ungoverned extravagance of irresponsible fishers who seek to harvest
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