A recent appraisal day held by Clarke Auction, of Larchmont, New York, yielded the exciting rediscovery of two lost paintings by 19th century Hudson River School artist Jasper F. Cropsey.

Missing for 150 years was Cropsey's "Autumn in America," a work from the artist's first series of four-seasons paintings that he executed in 1860 while in England, reports the auction house.

The second image, "Falls of Niagara," was unknown in Cropsey's ouevre although a preliminary pencil sketch for the painting was unearthed in the collection of the Museum of Fine Arts, Boston.

Both paintings have been authenticated and will be included in the Newington Cropsey Foundation's forthcoming catalogue raisonné.

Clarke will auction the paintings on May 15.