Streets of Laredo is basically the first part of Banks of the Devon. In the Kerr tune that part is mangled almost beyond recognition, but the second part (not used in any song of this family) is mostly intact. The tune for Saint James Infirmary is unrelated. I can't remember what Lloyd sang.

The tune for StJI is (at least at the start) almost the same as the one for Wayfaring Stranger - more than once I've started playing one of them and had people join in with the other. How did that happen?