There is a pretty bright star at Schwassmann's position (matching his description "perhaps * 10-11, sp surr m n"), but there must have been a defect involved, too. How else can we explain his comment "southwest [it is] surrounded by m[uch] n[ebulosity]" that he adds? There is nothing on the DSS aside from the star, so I am pretty confident about the defect.
An aside: I see from the big table that I had called this a merged double star at one point. That was a mistake. There is no trace of a companion on the DSS2 or the SDSS images. This is a single star.