Cozy (and Nearly Camouflaged) Bird in Nest, Old Real Photo Postcard

As should be evident by now, I love an old photo of a bird, and ever more so a bird in a nest--I do believe watching birds nest never gets old, and I think provokes the most tender and protective instincts in us as humans.  I'd guess this is a Robin, looking pretty cozy and well protected to me, though keen to being peeking in upon. Lovely.

5 1/2" x 3 1/2", very good condition. Unused back.