The Different Forms of Flowers on Plants of the Same Species

by Charles Darwin

TRIMORPHIC SPECIES.

Column 1: Name of species. Column 2: Ratio expressing the extreme differences in diameter of the pollen- grains from the two sets of anthers in the three forms.

Lythrum salicaria : 60.

Nesaea verticillata : 65.

Oxalis Valdiviana (Hildebrand) : 71.

Oxalis Regnelli : 78.

Oxalis speciosa : 69.

Oxalis sensitiva : 84.

Pontederia (sp.?) : 55.

Column 1: Name of species. Column 2: Ratio between the diameters of the pollen-grains of the two sets of anthers in the same form.