It is a 17-piece pattern originally by La Mode Illustrée for the waist, skirt, basque and sash. Part of a Victorian series of patterns with TheBarringtonHouse.org, this pattern is according to today's sizing standards. 3/8" seams are allowed. Best for advanced sewers or those accustomed to sewing historical styles.
In a sort of Advents-Kalendar way, I will post 'red' for each day of December through Christmas and link the image as closely as possible to EvaDress Patterns (in pattern tour form) available in the shop!
Here is the twenty-first not unlike Christmas Hard Candy Mix, Bustle Dresses per:
https://fripperiesandfobs.tumblr.com/post/170238307037/evening-dress-of-alexandra-princess-of-wales and https://fripperiesandfobs.tumblr.com/post/144217498604/evening-dress-1870s-from-the-fashion-museum
Sew the look using our 1869 Bustle Dress pattern, now in one style, but with a few alternates coming next year!
Above: Back view of the currently offered 1869 Costume pattern.
Below: Future variations coming from the same basic dress pattern, as for the 1869 Costume.