Referee's report by John Zachary Young, on a paper 'The effects of antero-posterior reversal of lengths of the primitive streak in the chick' by Michael Abercrombie Sectional committee: Physiology Recommended for publication in Proceedings. Some modifications are required. The appendix shouldn't be published in its current for as no-one will read it. [Published in Philosophical Transactions B, 1950]. Date received not given. 7 August 1949