Where\'s the seam on the tongue Pteruges? (Subarmalis)

[C. Apollonius Priscus]

If you examine the link in Theodosius' post above that shows a closeup of the Germanicus pteruges, you can see the difference in the sculpting. To me, the first layer with the Medusa heads looks softer, the second layer looks like metal plates. The hinges appear to be full length which seems kind of odd to me unless they were riveted to a relatively non-flexible backing. I think that would rule out cloth so leather? Metal plate?

Julius Caesar's statues seem to have a little semi-cylindrical roll at the top of each of the tongue pteruges which I could see as being a hinge of either a leather strap or a real metal hinge. Looking closely at all the photos above now gives me the feeling that the tongue ptergues are attached to the lorica. I think that this would be the most efficient way of fastening them since if they were attached to an undergarment, when one bent or twisted , the lorica would ride up or down and would attempt to slip over the plates or raised decorations. If they were attached to the lorica, they would maintain the same spacing and work as a unit. They would probably split wherever the lorica's seams are - which appears to be another puzzle...