R. Thomas Mayo Brewer was born in Boston over a hundred years ago, . and died, in his native city, at the age of 66, on January 23, 1880. Al- though he was essentially a New Englander, he was always interested in the fauna of the Pacific Coast--an interest reflected in the christening of the Brewer Blackbird and the Brewer Sparrow. This fact justifies, perhaps, the publication of a letter from him that came recently into the possession of the writer. It must not be forgotten that despite Brewer's immersion in the practice of medicine and his subsequent political, editorial, commercial, and book-pub- lishing activities, ornithology, and in particular oSlogy, always occupied a prominent place in his life work. It is necessary here only to refer to his papers in the Proceedings of the Boston Society of Natural History, to his ad- mirable (1840) edition of Wilson's American Ornithology, his own North Am- erican Ornithology, and to his large share in the uncompleted History of North American Birds to show the amount and quality of his contributions to zoology. Audubon, Nuttall, Cones, the elder Sclater, Salvin, and many another 'Father' of American ornithology were among his intimate friends and con- temporaries. The first-named frequently acknowledged the help he received from his young friend, Brewer, in the preparation of his monumental work on North American' Birds. "A friend in our cavalry" is, of course, Captain (later Major) Bendire, with whom Brewer long maintained a considerable corre- spondence. It will be remembered that it was Dr. Brewer who compiled, from these letters, for the Proceedings of the Boston Society of Natural liistory, vol. 18, pp. 153-168, Bendire's "Notes on the Birds of Camp liarney." This inti- macy between the two men however, was not fated to endure. They had a se- rious disagreement (see Coues, in The Osprey, 1, 1896, p. 113) due, no doubt, to the contact--flint upon steel--of a bumptious, aggressive but su;)er-sensitive German soldier with a frank but rather tactless and narrow-minded Bostonian. Nobody knows the merits--if, indeed, it could truthfully be said to have had any--of the quarrel; but it was eventually patched up by a common friend, Professor Baird, who possessed all the polished virtues that both the other B's lacked. lie, as Coues says, not only smoothed the ruffled plumes of the doughty German captain, but induced him to present his famous gathering of birds' eggs to the National 1VIuseum, there to be the nucleus of one of the finest collections in existence. Even among hard-boiled oSlogists a teaspoon- ful of honey, as says the Spaniard, wisely spread, will catch more flies than a barrel of vinegar! Here is the letter: 223 Beacon St., Boston. Jan 9th, 1877. My dear Sir;--Your kind favor of the 19th ult. reached me only last evening. You will notice by the address above that. I now have a home of my own once more, in which I have been comfortably settled two months today. I have had a new cabinet made and am in the midst of rearranging my collec- tions. It begins to look as if I were never to get through with them, as small accessions from Oregon, South-West Texas and other places have come, from time to time, to add o the confusion. I am very glad you have received such a very fine addition to your already mag- nificent collection. Have you one of the Smithsonian catalogues in which the birds of North America are given with a number corresponding to each specific name? If not I will send you one; but if you have, will you give me a list, by numbers, of your defi- ciencies? For instance, if you have no egg of Cathartes aura, write I in the list--if none of Accipiter Cooperi, write 15--if none of Chaetura pelagica, write 109, and so on. In this way I can know what you lack, and when I can supply it I wlll be glad to do so. I inclose my photo. taken two years ago. Poor as it is, it is the least bad of any I have ever had taken. I am glad the acorns reached you in comparative safety after their long wander- ings to Washington and back. I hope some of each kind may retain enough vitality to produce trees for your park. We have been having a regular old-fashioned winter. The last ten days of No- vember, the whole of December and so far in January we have had snow storm after storm, and very severe weather. Days in which the thermometer indicated higher than 20 ø or 25 ø have been exceptional--often not above 15 ø at noon, and a number of morn- ings at zero, and yet you are some ten or twelve degrees farther north of us! Cannot you be induced to write a paper on parasitic birds? You have so much material at hand in your own collection, you could make it very striking and novel I have three eggs of that wonderful Molothrus bonariensis (Gmelin) which lays round, white eggs in a parrot's nest, smaller ones thickly spotted with red dots in a sparrow's nest, oblong purple and brown blotched eggs in a thrush's--and so on. I am not a bit of a Darwinian bfit such facts as these are beyond my ken. If you have not the eggs of this Molothrus but will write a paper on this genera[ class, I will send you a colored drawing of the three greatest differences in the eggs of this species. You can prepare a paper so much more complete than any one else. ß I .will send you with this two skins (1/2' and 9) of Leucosticte ittorais. Our lumpers call it L. tephrocotis, variety tttorais, but as these same gentlemen insist that there is no perceptible difference between the sexes, one sees that they may blunder and blend in one two distinct species. I want your opinion as to the differences of the sexes in this case. I shall mark their sexes, but inclose in this their labels, as it is illegal to send them by mail other than by letter. These birds are very rare, and only, so far, known to occur in winter among our mountains. These are from Oregon, near Camp Harney, in the eastern part of the State, given me by a friend in our cavalry. Yours very sincerely, T.M. BREWER. At first glance the present writer thought the preceding (which was with- out complete superscription) might have been written to the elder Sclater, but the internal evidence points decidedly to Osbert Salvin. Moreover, Mr. w. L. Sclater, to whom the original was shown, agrees that it was not addressed to his father but to Salvin. It will be noticed, inter alia, that Brewer occasion- ally uses the capital initial (as in Accipiter Cooperi) for the specific adjective of a systematic name when the former is derived from a proper noun. Chicago, Illinois, March 10, 1923.