Materials and Methods

The plankton sample containing developing sprat eggs was obtained near the southern end of Tory Channel, Queen Charlotte Sound, at 1545 hrs on July 27, 1966. A 1m diameter nylon plankton net of 0.6mm mesh size was towed for 15 minutes between 0 and 30m in water with a surface temperature of 11°C. Amongst the catch were 118 clupeoid-type eggs which were transferred to jars of fresh sea-water and kept under observation (the water temperature varied between 11°C and 13°C during observations). A few were fixed in formalin at intervals of about 12 hrs, so that a series of developmental stages through to hatching was obtained.

Sixteen adult specimens of S. antipodum measuring between 86mm and 112mm body length (= standard length) were collected from a 1in mesh nylon gill net set near the surface in the Bay of Many Coves, Queen Charlotte Sound, at 2000 hrs on the same day as the plankton tow was made. Twelve specimens were females and four were males; some of the females exuded small quantities of colourless eggs when lightly stripped, but no sperm emerged from the males when similarly treated. The eggs were observed fresh and then fixed in 5 % formalin as were the fishes.