Lily bud. Light micrograph (LM) of a cross-section through a lily bud (Lilium sp.), showing the tightly closed leaves on the outside and the reproductive structures on the inside. The internal structures are the male and female organs of the flower. At the centre is the pistil, made up of three fused 'leaves', the edges of which curl inwards and bear the placentas (deep red patches). These in turn produce the ovules, or female sex cells, (not seen in this young flower). Surrounding the pistil are six male anthers, each of which have four pollen sacs filled with developing pollen grains, or male sex cells, (dark red spots).