Phyllotaxis: Its Quantitative Expression and Relation to Growth in the Apex. Philosophical Transactions of the Royal Society of London. Series B. No.629, Vol.235, pp.509-614. 8 text figures.

In printed wrappers as issued, a presentation copy initialled by Richards, corners slightly bumped. else a very good copy. *Phyllotaxis was a subject which had interested Alan Turing before he died, SEE : J. SWINTON in : Alan Turing: Life and Legacy of a Great Thinker edited by Christof Teuscher. 'In his reaction-diffusion systems he had the first and one of the most compelling models mathematical biology has devised for the creation process. In his formulation of the Hypothesis of Geometrical Phyllotaxis, work done by 1954 but not published until 1992, he expressed simple rules adequate for the appearance of Fibonacci pattern. In his last, quite unfinished work he was searching for plausible reasons why those rules might hold, and it seems only in this that he did not succeed. It would take half a life-time before others, unaware of his full progress, would retrace his steps and finally pass them in pursuit of a rather beautiful theory.'.