Studies on the inductive action of the early chick axis on isolated post‐nodal fragments

Effects of RNA on the developmental potentiality of the posterior primitive streak of the chick blastoderm.

“…The posterior segments on isolation do not realize their presumptive fate, but can be made to differentiate if grown in association with the inducing tissue, Hensen's node. 3 This has led us to use the pos-*S .0 . * A w @ FIG.…”