Few have enjoyed the opportunity of benefiting by the advice and assistance of a scientific friend so much as yourself; and no one, I must be allowed to say, has evinced so little inclination to profit by it. When I call to mind the repeated offers I have made you to correct the nomenclature of your birds, from the first time of our acquaintance, and recollect the dislike you appeared to have to receiving any such information or correction, I cannot but feel perfect surprize at you now wishing to profit by that aid, you have hitherto been so indifferent about. Let me however urge upon you one advise which, for your own sake, I should be sorry you despised. It is to characterize yourself, or get some friend to do so for you, all your new species. The specimens, you tell me, are now in England, & the task will be comparatively easy. I urge this, because you may not be aware that a new species, deposited in a museum, is of no authority whatsoever, _until its name and its character are_ published. I have repeatedly set my face against such authorities, so has Mr. Vigors, so has Ch. Bonaparte, and on this head we are all perfectly unanimous. Unless, therefore, this is done, you will, I am fearful, loose the credit of discovering nearly all the new species you possess, and this I again repeat, for your own sake I should be sorry for. To me, individually, your not doing so, would rather be advantageous. The more a book is quoted, the more is its merits admitted, and its authority established. it was on this account I so repeatedly requested the _use_ only, of a copy of your book, that it might have been cited in "Northern Zoölogy"[100] not having it—I could not therefore mention it. I shall always be as thankful to you as formerly for any information on the habits, economy, and manners of birds; but, as to _species_, I want not, nor do I ever ask, the opinions of any one. that is quite a different matter, and entertaining peculiar ideas on that subject, you must not feel surprised at my differing from you in almost every instance. My reasons will always be laid before the public. In the present case, we totally differ about _species_ of Woodpeckers. I shall not, however propitiate a favourable opinion from you, or any one, by a compliment and therefore I will wait for some species which you yourself will admit, which I shall then give your name to, I am rather glad you did not accept my offer, for I am _now_ assisting in bringing out an Octavo edition of Wilson, by Sir W Jardine which will be arranged according to _my_ nomenclature. Yours my dr Sir Very faithy W SWAINSON