These are showing a revival of the Dolly Varden dress, a style that is named after the character in Charles Dicken's book Barnaby Rudge. These dresses were popular in the 1870's. There was quite a fad, the name shows up in songs, on stage and there is even a trout we still call a Dolly Varden.
Since this is from The Ladies' Home Journal dated 1902, these gowns were a look back. It's too bad these aren't in color since "The term Dolly Varden in dress is generally understood to mean a brightly patterned, usually flowered, dress with a polonaise overskirt gathered up and draped over a separate underskirt.".
These are designed by a Mrs. Ralston and illustrated by Thomas Mitchell Peirce, the same artist who did the bride on the cover.