Autonomous feeding and morphological
changes characterized the larval stage. A relatively
broad space appeared between the head and anterior
margin of the yolk sac. The yolk sac was elongate,
oval in thorasic region and became cylindrical in
abdomen and occupied about 1/3 of the body from
the anterior end. At this stage the outline of the brain
in the cranial cavity could clearly be seen under a microscope. When 8hrs old the vent and gill rudiments were formed. Gut was straight to slightly curved in anterior portion. Air bladder was shallow, behind pectoral region, which develop into two chambers in the post larval stage. Pigmentation was more pronounced throughout the head and body. The larvae attained free movement with the help of fins when 8 hrs old. The larval development is summarized in Table 2.