Ask whether there is a section of the frame that changes your sense of the portrait when viewed on its own. Take a second pass through the gallery and see which portraits remain clearest in your memory.

A portrait from the featured image sequence
A study from the portrait series
A portrait from the photo gallery
A portrait in the featured selection
A portrait included in the image series
A study in the gallery selection
A portrait chosen for the image series
A portrait in this collection
A figure study from the portrait gallery
A selection from the portrait studies