I'm not 100% certain on this one, but will give you a guess. It appears to be one of the wild violets. One reason I'm not certain is because there are so many different kinds, and I'm not that familiar with the Catskills.
My not so certain guess is "Small White Vi
olet" (Viola macloskeyi var. pallens ).
Here is a link where you can look at pictures. https://www.minnesotawildflowers.info/flower/small-white-violet
Let me know if this is it or not.