This miniature portrait is by Walter Ferris Biggs (JFM 1851->1910). It is signed on the front "Biggs 1900" and is inscribed on the reverse; "Luna Alston de Gallegos painted by Walter Ferris Biggs year 1900".
Walter Ferris Biggs (not to be confused with the American artist Walter Biggs (1885-1968)) is not mentioned in Blattel's dictionary.
However by using family history sites and the Internet it has been possible to assemble a little about him.
Biggs was born JFM 1851 in Islington, London, England, where his father Charles Ferris Biggs was a lace and flowers warehouseman, presumably the flowers being artificial.
In the 1851 census Charles and his wife Sarah Jane lived at 31 Gibson Square and had four sons aged four or under; Charles Neville, Fred William, Walter Ferris, and Henry. To assist with the children, they had a general servant and a nurse girl aged 13. This nurse girl, Elizabeth Malcolm, was from Scotland and seems to have been a long way from home for a 13 year old.
For the 1861 census, Biggs, was at Bickinshill boarding school at Dymock, near Bristol in Gloucestershire.
It is hard to find census references to Walter Biggs after 1861 until he turns up in the 1910 United States census. However, his parents seem to have continued living in England, in the 1881 census with Walter's father living as an auctioneer and land agent at 8 High St Lewisham, with his wife Sarah Jane, and two daughters.
In the 1910 census Walter F Biggs is a painter of portraits living as a boarder in Philadelphia. His wife is not with him, but he states his present marriage has lasted 19 years, suggesting he was married in 1891. He also states he arrived in the United States in 1871 and is naturalised.
A clue to his whereabouts in the intervening years is found from the Internet, where he appears to have married Elisa Moore y Sinnot (1867-1944) in Argentina Edward Moore & Eliza Sinnott
It therefore seems Biggs may have painted portraits in both Argentina and in the United States.
References have been found to him as the teacher of Luna Alston de Gallegos, see Inmigración y plástica: los pintores - Monografias.com
The miniature portrait is a very useful reference document as it actually depicts Luna Alston de Gallegos (1881-1978) who was also a miniature painter in Argentina. There are several miniatures by her in this collection in the American 20C Gallery, including the one showing here. In her career she painted over 400 miniatures.
A comparison of the two miniatures enables one to determine that the miniature by Luna, where the sitter was unidentified when purchased, is in fact a self-portrait by Luna, probably painted several years after the portrait by Walter Ferris Biggs. 1301