Note: Sid Lethbridge: Attribution based on the following trade quote: “February 21 1884 American pottery and glassware reporter "Bryce Bros., have now ready their new set, Monarch, and the name is an appropriate one, for it surpasses all their previous efforts. The sides of the pieces are plain glass, of oval shape, and they overlap the ends, which are moderately convex in form. This is a novel venture, and can be found in no other set. The pieces rest on four separate feet, diverging from nearly a common center, and they have no stem......

The reference to "no stem" above is appropriate for the table set and nappies etc. but not for the high standard comport.
Further support for Bryce Bros. is that this pattern can be found in amethyst, a colour that just a few companies made.