This Dwig card is from series 21, published by Charles Rose. I call this series the Man in the Moon series because all the moons have faces. I think there are only four cards in the series, I only have four and have never seen any other ones for sale anywhere.
The girl has blonde hair, which is part of the reason I like this card so much. It is the card I have always had as my avatar picture on WordPress. I feel like most of Dwig’s fancy girls have dark hair, with the occasional blonde mixed in. It got me thinking, blonde hair probably wasn’t as prevalent in the early 1900s. 😉 A quick Google search shows that the first commercial hair dye was invented in 1907, one year before this postcard was published. I know my hair wouldn’t be as blonde without it!