Myogenesis and neurogenesis in the chick embryo: A comparative study.

An electron microscope study of the comparative development of muscle and nerve tissue in the pectoral and wing regions of the chick embryo has been performed. Neurogenesis in the pectoral region is seen to be about 2 days advanced over that in the wing. Myogenesis proceeds at approximately the same rate in both areas. Myofibril organization and myotube alignment appear to be independent of developing nerve tissue.An incidental finding is that of aggregates of poorly organized myofilaments inserted into otherwise mature myofibres. It is suggested that this may be a method of increase in muscle length.