Biochemical investigations of the Australian oyster, Saxostrea commercialis

Abstract

The work detailed in this thesis is a part of the oyster research programme of the C.S.I.R. Division of Fisheries, and the sections covered here include metrology, hydrology and biochemistry. Though the work is conducted from a viewpoint which is of a definite economic nature, the programme is based upon lines which embrace fundamental biological studies and this general summary is, in reality, a background to these studies. Though there are a number of different species of oysters to be found at various places along the coast of Australia there is only one which is of economic importance. This is the Sydney Rook Oyster (Saxostrea commercialis) which is found most abundantly along the East Coast. This species is hermaphrodite and in the work now progressing it is a comparatively easy matter to establish seven sex-classes; these embrace the transition of pure male to pure female. In the reproductive period the sexual products are spawned into the water and it is there that fertilisation occurs. Embryonic and larval life, lasting about a fortnight, is pelagic and at the end of this period "spat-fall" takes place, is, the larvae settle upon a suitable substrate and undergo metamorphosis.