Experiments on the development in vitro of the avian knee-joint

Abstract

The subject of joint-formation, about which there has been much speculation and conflicting hypothesis, involves two main problems: (1) He question whether the characteristic shape of the articular surfaces is due to extrinsic or intrinsic factors. (2)The question how two opposing bone rudiments developing from a common block of mesoderm are able to separate and form two movable, independent units, instead of developing in continuity.