Foundational Studies On The Embryonic Development Of The Mud Crab, Scylla Serrata(Forsk(?)l)

Scylla serrata(Forsk?l,1775) is an important econimic aquatic breeding crab. Embryo takes a significant position in individual ontogenesis.With the histological techniques,optical microscopy,electron microscopy,in vitro culture techniques,a systematical and fundamental study was made on the embryonic development of Scylla serrata.The main results as follows:1.The female crabs of Scylla serrata usually ovulated during the time of evening to dawn.As the mature oocytes passed through the gonopore and immerged into sea water,whether fertilized or not, their vitelline membranes swelled and formed chorin, immediately the structure and character of chorin changed greatly:with the considerably swelling of chorin , micropores appeared at the incontinuous exochorin;while some of glue,which were produced by endochorin disadensifying flocculent materials, penetrated through the micropores and attached chorin,so chorin became sticky,pliable and extended.With the rapid abdominal pumping of the ovigerous females and the water flowing,a portion of chorin became deflected off the egg's surface,then chorin and its wrinkles were entangled with each other or caught by ovigerous setae and formed funiculuses and egg stalks respectively.Funiculuses and egg stalks mentioned here,were the different extensional part of chorin,which finally condensed and concreted to form a tough and durable material capable of anchoring the egg mass to the pleopods.We firstly demonstrated the existence of micropores and glue of oocyte in crustaceans, which approved the sticky glue for attachment was from the eggs themselves, and we developed chorin conglutinated-condensed-solidified theory of egg attachment.2.The second envelope,the fertilization membrane(Fm),formed between oocyte and chorin during a complex cortical reation initiated after fertilization.The cortical reation includes the successive exocytosis of two morphologically different granules.Firstly the dense granules undergone exocytosis and formed a thin membrane.As followed that,the ring-shaped granules undergone several rounds of...