In completing the third volume of the ' Avifauna of British India' the Author feels that the most difficult part of his work has been accomplished and it seems an opportune moment to express his thanks to all those who have helped him. In the first place his gratitude is due to the authorities of the Natural History Museum who have done everything in their power to facilitate the execution of his work and to place at his disposal the unrivalled collections of Indian birds and the magnificent library. To the Staff of the Ornithological Section he is deeply indebted for the constant assistance given and the courtesy shown him and he would like especially to mention Dr. P. Lowe, Mr. N. Kinnear and Mr. J. Wells. To Dr. Hartert and others who have kindly read portions of his manuscript his thanks are also due whilst he recognizes that it is almost impossible to realize the immense amount of work that has fallen upon the Editor, Sir A. E. Shipley, especially in the way of proof-reading, carried out with a thoroughness and success which would have been impossible had he not had at his disposal the resources of a great University as well as those of the finest Libraries and Collections within the Empire.
The Author would like to draw attention to the fact that in any work on Natural History it is impossible to design any sequence for orders, families and genera which shall be entirely satisfactory. Unfortunately for the Ornithologist,, no consecutive arrangement of Families can give a proper idea of how they interlink, one into another ; the only satisfactory manner of dealing with the Aves would be by a genealogical tree, branching in all directions from the one great parent branch.
E. C. STUART BAKER.