When Ahumado is bitten by the Brown Recluse spider (The Spider Who Hides) he looks at the wound right away. There is already a large black spot with a red ring. It takes at least several hours for a bite from this spider to look like this.
Val Kilmer sings The Skye Boat while getting his head shaved. As this is based in the 1850s, the song wasn't written until the 1880s by Sir Harold Boulton.