It seems to be Westmoreland, English Hobnail (Line #555). There are two bowls of this shape listed in Lorranine Kovar book on Westmorland Glass 1950 - 1984 (one of a series I believe).
The larger of the bowls has EH-65 code number the smaller one EH-66.
The mark should be a 'W' with a 'G' superimposed over the 'W', however the book does warn about reproductions from other American factories who tend to use similar marks.
I have just found a description of the codes at the rear of the book.
EH65: rose bowl, 6", flat, cupped rim, 4. 1/2" tall.
**Colours: Crystal. milk glass
Availability, All available
Reproductions: Turquoise blue, cobalt blue and possibly others.
EH66: Rose bowl, 4" dia x 3" tall, flat, cupped rim
**Colours: Crystal, milk glass, pink pastel
Availability: All Available
Reproductions: Turquoise blue, colbalt and possibly others
flat refers to the base, Line #555 had round bottom bases, Line #555/2 had square bottom bases (looks like yours), and Line #555/3 were mostly stemware and also barrel shaped.
Crystal (the first production line) refers to clear glass.
The text part of the book lists these Westmorland colours: turquoise, cobalt (very rare - hence the repros mentioned above), light green, pink, milk glass, blue mist, golden sunset,lilac pastel, blue pastel, ruby, pink mist, brandywine blue, laurel green, purple marble, moss green, antique blue milk, black milk glass (don't blame me for that one :roll: ), crystal with black flashed bases and crystal with red flashing.
** The book does not make clear why there are only a few colours listed under the 'code' descriptions - maybe those are the only ones the author has got or seen. I assume under the code description that "All available" means all colours.
The book itself, I purchased this several years ago when I was researching Nazeing as there were one ot two items simialr to their pressed glass products. I believe there was at least one other book in the series, covering a different (possibly earlier) timescale, it came from Frank and Shirly when they were trading in Luton. I have seen them at Fairs (e.g. Newark) but I do not know if they still trade in books.
My copy will appear on Ebay in the near future as I don't jhave any further need for it.