The Latin word for vein is vena and refers to the veins that can be seen in the butterfly wings. Cools has collected these wings in recent years. The butterfly wings found are then stripped of its scales, so that the veins become visible. During a research together with the Maastricht Science Programme at the University of Maastricht, Cools discovered that
the veins are filled with meconium during the butterflies' development.
When it has hardened, this gives firmness to the wings through which the butterfly can fly. The work not only shows the result of a scientific research in a different form, but above all shows the vulnerability of this fragile animal.