Copy letter from Robert William Frederick Harrison to Le Directeur des "Rendiconti", Circolo Matematico di Palermo 30, Via Ruggiero Settimo, Palmeri, Italy 'Dear Sir, With reference to your letter of April 13th, requesting the regular despatch of Proceedings [of the Royal society] Series B (Biological Section) as a gift to the Cricolo Matematioc, I beg to inform you that in view of the large exchange list of the Royal Society, it has been considered advisable to restrict the issue of the two series where possible. Consequently, the B series of the Proceedings is not sent to Mathematical Societies, but only the physical science section. The Royal Society will have pleasure in continuing its present despatch of [Philosophical] Transactions [of the Royal Society] A Series, and Proceedings A Series to the Circolo.' 23 April 1910