  Recently singular solutions have been discovered in purely elongational flows
of visco-elastic fluids. We surmise that these solutions are the mathematical
structures underlying the so-called birefringent strands seen experimentally.
In order to facilitate future experimental studies of these we derive a number
of asymptotic results for the scaling of the width and extension of the
near-singular structures in the FENE-P model for polymers of finite
extensibility.
