The musculature and vascular systems of two species of Cambrian Paterinide ( Brachiopoda)

Two species of Paterinide brachiopod preserving details of the musculature and vascular systems have been studied. Their dorsal valves are shown to have a large quadripartite muscle field not unlike that of the articulates with further scars located on the inner face of the apex of the homeochilidium. The dorsal vascular system is possibly saccate (apocopate). The ventral muscle field has two short subtriangular scars divided from one another by the proximal portions of main vascular canals. The location of other scars is uncertain. The ventral vascular system is probably saccate. - Author