These are some of the illustrations of Lee Brown Coye (1907-1981) for August Derleth's anthology of macabre tales, Who Knocks? Twenty Masterpieces of the Spectral for the Connoisseur (Rinehart, 1945). Coye was well known for his work illustrating Weird Tales in the forties and fifties and this was not the only Derleth anthology he illustrated. For me, they have just the right mixture of illustration and abstraction to match the not/real qualities of a supernatural tale. As his wikipedia page points out, although he was best known for this kind of work he was also a painter, silversmith, photographer, muralist... etc. etc.