Longitudinal Section of the Larva of the Lancelet at the Beginning of Development

Lancelet Cross Section Through the Branchia and Middle Intestine Regions

Lancelet

Longitudinal Section of the Larva of the Lancelet in Advanced Development

Lancelet – Equal Cell Division and Formation of Nuclear Membrane

Chromosome Model

Change of Nuclear Phases in the Maturation of Sperm and Ovum (Meiosis)