I call this simply The Magenta Dress.
It is on the cover of the British edition of Nineteenth Century Fashion in Detail, by Lucy Johnson. I love everything about this gown. The color. The style. The textural contrast between the silk body and the satin ribbon trim. The pop of off-white nets poufs on the sleeves. Bows everywhere. Scallops galore. And did I mention the COLOR?!
It appears to have been made with two different bodices, one for “everyday” and one for special occasions; not unusual for the time. Enjoy!
Update: Hokey smokes! Someone actually reproduced this dress! Here’s the link to her blog: http://koshka-the-cat.blogspot.com/2012/09/the-1869-dress-day-version.html