Simpliglottis cornuta (was called Chiloglottis cornuta) - often found by the sides of bush tracks, its leaves close to the ground.

Flowers in the summer; self-pollinating.

A closer view of the flower. An Australian recently told me that they call this orchid the "bird's mouth orchid". It is easy to see why.

Those dark round things are called calli - (pleural for callus, meaning thickened tissue).