Elaeocarpaceae
![Tetratheca ciliata](https://www.latrobe.edu.au/_media/corporate/dept-of-maths-and-stats-images/Tetratheca-ciliata.jpg)
Tetratheca ciliata
Tetratheca ciliata is known commonly as Black-eyed Susan or as Pink Bells. Each flower has four dark purple stamens but pollen is not usually found on the outside of these. The anthers have a circular hole at the top and may well operate by buzz-pollination. To operate such flowers, the insect has to produce a sound of a certain frequency and this dislodges the pollen. Bees are likely candidates for such pollination mechanisms but no major pollinator for Pink Bells has been identified.