Species:

Platynereis, probably bicanaliculata

Frame rate:

12 sec/frame @ 30 fps = 360-fold time-lapse

Points of interest:

Unequal spiral cleavage; gastrulation by epiboly

Optics:

40x water-immersion, Zeiss DIC, Hamamatsu C2400

Filmed by:

George von Dassow

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