To G. B. Murdoch   13 March 1871

Dear Sir

I am much obliged for your valuable letter. I am strongly inclined to think that I have made a great & complete oversight with respect to the subject which you discuss. I am the more surprised at this, as I remember reflecting on some points which ought to have led me to your conclusion.¹

By an odd chance, I received the day before yesterday a letter from Mr Lowne (author of an excellent book on the anatomy of the Blow-fly) with a discussion very nearly to the same effect as yours.² His conclusions were drawn from studying male insects with great horns, mandibles &c. He informs me that his paper on this subject will soon be published in the Transact. Entomolog. Soc.³ I am inclined to look at your & Mr Lowne’s view as specially valuable from probably throwing light on the greater variability of male than female animals, which manifestly has much bearing on sexual selection. I will keep your remarks in mind whenever a new edition of my book is demanded.⁴

With my best thanks | I remain my dear Sir | In Haste | yours very faithfully | Ch. Darwin.