Here my husband, Bill, is cleaning a deer tenderloin. He’s lifting up the superficial fascia, which is fragile and easy to separate. Underneath is the deep fascia which is much denser and firmly adhered to the muscle. The deep layer looks like one thick layer, but it is actually multiple layers of criss-crossing collagen fiber bundles. If you look at it closely you may be able to identify these crossing fibers.
Deer tenderloin with fascial layers