No credit for Special effects of any kind, although I think Alex Weldon was responsible for pyrotechnic and mechanical effects.
Edward Small productions from the 40´s, and early 50´s used to be distributed by Columbia Pictures (Black Arrow 1948, Lorna Doone 1951), but latter on he worked for United Artist (Salomon and Sheba 1959, Jack the giant killer 1962, or Timbuktu 1958) All those films have matte painting, but as far as I know United Artist didn’t have FX department, and Columbia used to assign matte works to a freelance artists or commission works to other studios matte departments.
At some other films by Edward Small (The man in the iron mask 1939 or The Corsican brothers 1941) FX credit were for Howard Anderson Company. As far as I know many matte artist worked for H. A. Company including Albert Whitlock.
These three matte paintings could have been done by any artists that used to get works from out of his department like Jan Domela, or any freelance matte painters like Howard Fisher, Cliff Silsby, Louis McManus, or Albert Maxwell Simpson.