An equal parts (Fifty-Fifty) Dry Martini with a hint of orange due to the use of orange curaçao, orange bitters and an orange zest twist.
The earliest known Marguerite Cocktail recipe appears in Harry Johnson's 1900 Bartenders' Manual.
(Use a large bar glass)
Fill glass 3/4 full of fine-shaved ice;
2 or 3 dashes of orange bitters;
2 or 3 dashes of anisette;
1/2 wine glass of French vermouth;
1/2 wine glass of Plymouth gin;
Stir up well with a spoon, strain into a cocktail glass, putting in a cherry, squeeze piece of lemon peel on top and serve."
Then in his 1903 Bartenders Encyclopedia, Tim Daly omits the anisette in his recipe for the Marguerite:
Use a mixing glass.
Half fill with fine ice.
2 dashes of orange bitters.
1 dash of orange curacoa.[sic]
½ wine glass of French vermouth.
½ wine glass of Plymouth gin.
Stir well with spoon, strain into a cocktail glass, twist a piece of lemon peel on top, and serve."
The Marguerite, then turns drier and by the 1904 Stuart's Fancy Drinks it becomes 2/3 Plymouth gin [a dry gin] to 1/3 French [dry] vermouth. Basically a modern day 2:1 Dry Martini.