Age, 13.4 days.

Standard length, 4.00 mm. Length of caudal fin, 0.79 mm. Mesencephalon width, 1.05 mm. Depth of yolk, 1.19 mm.

The yolk mass is further reduced, and there is a concomitant regression of the extra-embryonic membranes to form a “neck strap,” covering the posterior one-third of the eye and extending posteriorly to cover most of the mesencephalic region. Fin rays in the anal fin make their first appearance here.