I purchased this one from a favorite dealer in Pennsylvania this summer, with the very soft, watery watercolor on this rose colored body and pale blue wings of this bird completely doing it for me. I did find one record for an Anna L. Erb (Mother of Esther Erb Wenger) born in May, 1848 in Lancaster County, and there are lots of records for Erbs around those parts, including a few other Annas born in and around 1848.
10 15/16" x 8 13/16" framed. Very good condition, period frame, original glass, original wood back, wired for hanging.