My dear Wallace,--I have thought that you would perhaps like to see enclosed specimen and extract from letter (translated from the German by my son) from Dr. W. Marshall, Zoological Assistant to Schlegel at Leyden. Neither the specimen nor extract need be returned; and you need not acknowledge the receipt. The resemblance is not so close, now that the fragments are gummed on card, as I at first thought. Your review of Houzeau was very good: I skimmed through the whole gigantic book, but you managed to pick out the plums much better than I did for myself. You are a born critic. What an _admirable_ number that was of _Nature_. I am writing this at Sevenoaks, where we have taken a house for three weeks and have one more week to stay. We came here that I may get a little rest, of which I stood in much need.--Ever yours very sincerely, CH. DARWIN. With respect to what you say about certain instincts of ants having been acquired by experience or sense, have you kept in mind that the neuters have no progeny? I wish I knew whether the fertile females, or queens, do the same work (viz. placing the eggs in warm places, etc.) as the neuters do afterwards; if so the case would be comparatively simple; but I believe this is not the case, and I am driven to selection of varying pre-existing instincts. * * * * * _The Dell, Grays, Essex. November 15, 1872._ Dear Darwin,--I should have written earlier to thank you for your book,[94] but was hoping to be able to read more of it before doing so. I have not, however, found time to get beyond the first three chapters, but that is quite sufficient to show me how exceedingly interesting you have made the subject, and how completely and admirably you have worked it out. I expect it will be one of the most popular of your works. I have just been asked to write a review of it for the _Quarterly Journal of Science_, for which purpose I shall be in duty bound to seek out some deficiencies, however minute, so as to give my notice some flavour of criticism. The cuts and photos are admirable, and my little boy and girl seized it at once to look at the naughty babies. With best wishes, believe me yours very faithfully, ALFRED R. WALLACE. P.S.--I will take this opportunity of asking you if you know of any book that will give me a complete catalogue of vertebrate fossils with some indication of their affinities.--A.R.W. * * * * * _Down, Beckenham, Kent. January 13, 1873._