Another wee beastie.

This time it looks like a Mottled Umber moth (Erannis defoliaria ).  The females are wingless moths!  Darkness of wing colour in the adult moth varies and, as with the peppered moth, the darker forms tend to be prevalent in industrial areas (Wikipedia).  This one was on one of the Ulnus laevis.  Bit nervous about the 'defoliaria' in the name ('can be a problem in orchards').