Letter from Solly Zuckerman, on a paper 'The transplantation of normal tissues: with special reference to auto- and homotransplants of thyroid and spleen in the anterior chamber of the eye, and subcutaneously, in guinea-pigs' by Michael Francis Addison Woodruff and Hazel G Woodruff to David Brunt Apologises for the late return of the paper , as he was in the United States for a week and has just returned. He agrees with Medawar's criticisms but despite this, believes that the authors reach conclusions of importance. Medawar thinks the paper should be teared into different pieces and presented in more than one part, but he is rather more lenient. The paper deserves to be published. Medawar is right that the paper could be improved, but it is 'nevertheless interesting and useful as it stands'. [Published in Philosophical Transactions B, 1950]. Endorsed on recto as received 5 October 1949. 4 October 1949