What does Honda mean when they say "seal rubber"

[mithril]

I'm doing a top end rebuild of a Honda Elite CH80. In the manual the instructions for the installing the head say "Install the gasket" followed by "Install the seal rubber." The image that accompanies it shows the "seal rubber" around the part of the gasket sealing the cam chain gallery.

What isn't clear to me is if this should be some type of O ring or permatex?

The replacement head gasket I purchased has a raised rib on this section of the gasket, does that mean I can ignore installing the "seal rubber" as It's already there? The manual doesn't explain this at all.

Thanks
Mithril