Vorticity contour and velocity vector plot of flow during maximum contraction for a small and large "Chiropsella bronzie". Flow emerging from the bell of the small medusa is characterized a simple jet (i.e.; jet of fluid and a single vortex ring). Flow generated by the large medusa is more complex with the stopping vortex from the previous swim cycle interacting with the starting vortex generated during bell contraction and flow entrained from the bell margin by the velarium (inset) contributing to the starting vortex. Inset: close-up of entrained flow in region adjacent to velarium. Note that the maximum velocities (red) are oriented toward the inflexion point of the velarium.