odd chant notation

[rayates55]

Does anyone know what this form of chant notation is called or any resources for interpreting it?

[benwiggy]

I suspect it's just a stylized Pes, e.g. lower note, then higher note.

The downward ones I'm less sure, but again probably a Clivis.

Here's a modern version, which is similar, but not identical; though you can see what's going on.

Screenshot.png (82.26 KiB) Viewed 4865 times