Non-neural influences in the determination of chick skeletal muscle.

The technique of chicken-quail hybridization in "in vitro" cultures was used. Muscle differentiation of 9 H.H. chick embryo somites without the participation of nerve fibres was noted when they were cultured in the presence of quail pectoral muscle cells. It is suggested that this non-neural model may also be valid "in vivo", and that it probably interacts with the neurodependent mechanism demonstrated in a previous paper.