REARING OF BIVALVE MOLLUSKS
27
Early development of the egg of M . 80&ii88inza is basically the
=me as that of many other bivalves. After dissolution of the germinal
vesicle (Fig. 13b) the size and shape of the egg remain the same. If
Mactra (Spisula) solidissima
Fro. 13. Development of Mactra (= Spisula) S o ~ i d i . ~ m m a
from unfertilized egg (A) to
Diameter of egg is about 58 p, while length of early
straight-hinge larva (H).
streight-hinge larva is about 79 p. Dettrilrct dewription in text.
the fertilized egg is kept in water of about 20°C, the polar body is
formed in about 45 min (Pig. 13c) end the two-cell stage, meaeuring
about 65 p along the longest axis, is reached in 90 min (Fig. 13d).
27
Early development of the egg of M . 80&ii88inza is basically the
=me as that of many other bivalves. After dissolution of the germinal
vesicle (Fig. 13b) the size and shape of the egg remain the same. If
Mactra (Spisula) solidissima
Fro. 13. Development of Mactra (= Spisula) S o ~ i d i . ~ m m a
from unfertilized egg (A) to
Diameter of egg is about 58 p, while length of early
straight-hinge larva (H).
streight-hinge larva is about 79 p. Dettrilrct dewription in text.
the fertilized egg is kept in water of about 20°C, the polar body is
formed in about 45 min (Pig. 13c) end the two-cell stage, meaeuring
about 65 p along the longest axis, is reached in 90 min (Fig. 13d).