As is evident, this is the cover of an issue of Thrilling Mystery magazine. Specifically, it’s the August 1936 edition, as indicated here. A modern reproduction of the cover is available for purchase, but no information on the cover artist is available. Text on the cover reads “Thrilling Mystery. Spawn of the Slime: A Horror Novelette of the Evil Seas byHal K. Wells. Food for the Wolf, a Novelette of Howling Terror by G.T. Fleming-Roberts. The Grave Gives Up, A Novelette of the Living Dead, by Jack D’Arcy. Featuring City of Creeping Death, a Weird Mayan Novelette by John H. Knox.”
Image provenance by Bacchus at Erosblog.