I was looking at the pictures posted by Katherine, and noticed in one
of them, when I zoomed in closely and looked at the two women on the
bottom…

http://pics.livejournal.com/jillwheezul/pic/000sezrh/g34

Is that side lacing (or holes for side lacing) that I'm seeing? Her
dress is colourless, but the red ink picks out a series of holes on
either side of what looks like a slit.

It seems like such a strange detail for the artist to depict, when the
dresses are otherwise completely plain.