Spinal cord is known to promote muscle differentiation.
To test the question, regenerating limb blastemata of varying ages were transplanted to the dorsal fin in company with segments of anterior spinal cord. Patterns of muscle fibers did not suggest limb-type morphology. While myogenically competent cells appear to contribute to the blastema, doubt exists that these are the very same cells that would have produce muscle in the normal limb regenerate. Regeneration of the salamander limb is a phenomenon attended by a large, conjectural and speculative literature. Decisive evidence in support of the latter opinion is lacking.