This may be Mabel Browne, stepdaughter of Countess of Lincoln Elizabeth FitzGerald. Mabel Browne’s Wikipedia article is here. Her article in thepeerage has a portrait found in the Elizabeth Fitzgerald Subalbum, here, that bears a very strong resemblance to the portrait below on this page.
From artuk.org; filled in shadows to resolve false sleeves and brought out details of wheel and skirt in the process.
British Ladies are pushing farthingales to their limits with strong colors such as Lady Browne’s embroidered bodice and black- and red-rosettes. Her dress does not have hanging sleeves.
Keywords: Mabel Browne, Countess of Kildare, Browne family, FitzGerald family, Countess, British, straight coiffure, earrings, necklace, fitted bodice, partlet, high neckline, lace neckline ruff, chemise, modesty piece, U-neckline, fitted bodice, U-décolletage, stomacher, revers, rosettes, draped jeweled bodice ornament, tabbed strap upper sleeves, long tight rolled lower sleeves, cuffs, back-flared lace cuffs, bracelets, deep vee waistline, wheel farthingale, lace-edged handkerchief