It is a poorly butchered rack of lamb. The spine should have been removed before packing. Very few people would have the knowledge to remove it at home. It is normally roasted just like a rib roast from a steer.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
Whip It Off, Chambers!
"perhaps...but then again...maybe not..."