He therefore interpreted the "triangles" as short, fleshy, conical legs (lobopods). He also found small mineralized patches at the tips of some, and interpreted these as claws. Under this reconstruction, the gill-bearing flap and lobopod were homologized to the outer gill branch and inner leg branch of arthropod biramous limbs seen in Marrella, trilobites and crustaceans.[5] Zhang and Briggs (2007) analyzed the chemical composition of the "triangles", and concluded that they had the same composition as the gut, and therefore agreed with Whittington that they were part of the digestive system.