Armor of the Divine Triad : lamellar armor

[Dan Howard]

c) do I need a subarmalis? Yes.

Only for a segmentata. Other armours work perfectly well with a liner made of a few layers of linen (or leather). Scale armour had its own liner. Greek plate cuirasses had their own integrated liners and there is no reason to think that Roman ones weren't made the same way. IMO Roman mail also had its own integrated liner. That's why it is depicted with that leather edging.