This pattern is copyright 1963 but the skirts are current looking. Skirt silhouettes do change, but this style is still going strong. And notice, even with the boxy tops, there are darts for shaping. There are a total of 4.
Here's the back of the envelope:
And this pattern is dated 1959. Both views represent the grandest examples of robes that I've ever seen. Actually they are described as "housecoats" on the envelope. Is there a difference or has the terminology changed?
Can't you just envision the long one made up in silk satin?
This design is constructed with a bodice and skirt, and the skirt has 7 large, very flared gores, as shown on the back of the pattern envelope. I can't imagine wearing "foundation garments" (shapers in today's terms) under the robe to create the hourglass silhouette of the fashion illustration.