  A rich zoology of shapes emerges from a simple stretched and twisted elastic
ribbon. Despite a lot of interest, all these shape are not understood, in
particular the shape that prevails at large tension and twist and that emerges
from a transverse instability of the helicoid. Here, we propose a simple
description for this cylindrical shape. By comparing its energy to the energy
of other configurations, we are able to determine its location on the phase
diagram. The theoretical predictions are in good agreement with our
experimental results.
