Copy letter from Robert William Frederick Harrison, to J P Hill, Zoological Laboratory, University College, Gower Street, W.C. In answer to Hill's enquiry, Hill's joint paper with Professor J T Wilson on Ornithorhynchus is in hand for publication and Harrison is obtaining estimates for the illustrations. Notes Hill's request as to the numbers of proofs Hill and Wilson desire, but does not expect them to be ready for a month or two. 12 October 1906