THE STAGES OF JACK MACKEREL EGG DEVELOPMENT 



The continuum of egg development is divided into a series of 

 arbitrarily but rather precisely defined stages (fig. 2). The 

 primary reason for staging eggs is to determine the relationship 

 between rate of development and temperature. This is needed in 

 order to determine the number of days' spawning represented in 

 each sample. The method is also useful for determining the period 

 of the day during which spawning takes place. 



Only selected stations are given since stations were deleted 

 for various reasons, among which were poor preservation of material 

 making staging unreliable and poor temperature records. 



