idealized flower

real flower, relatively primitive form

pentamerous flower (5-merous)

tetramerous flower (4-merous)

trimerous flower (3-merous)

loss of a whorl (notice perianth)

loss of a whorl in wind-pollination

reduction in size of parts (Amaranthus)

unisexuality (red maple)

unisexuality; animal pollination (squash)

squash male flower

wind-pollination syndrome (Alnus)

hazelnut female inflorescence

oak male catkins

Lemna minor female flower close-up

aggregation of tiny flowers (Zinnia)

Euphorbia pseudanthia (cyathia)

Euphorbia cyathium explained

perianth elaboration (Epiphyllum)

perianth elaboration (Nymphaea)

perianth elaboration (orchids)

elaboration of all whorls (Magnolia)

elaboration of all whorls (Passiflora)

elaboration of receptacle (Fragaria)

Fragaria close-up

Fragaria even closer up

calyx coloration (Fuchsia)

petaloid calyx with nectar spurs (Aquilegia)

petaloid filaments (Mimosoid legumes)

actinomorphy (Oxalis)

actinomorphy (morninglory)

zygomorphy (Salvia)

zygomorphy and nectar guides (foxglove)

connation (sympetaly)

sympetaly and zygomorphy

zygomorphy, adnation (orchids)

apocarpy

apocarpy

syncarpy (melon; 3 carpels)

adnation (epipetaly)

hypanthium and ovary position

epigyny (Fuchsia)

epigyny (Narcissus)