not survive long, though it has to be admitted that, at the present time,
the system is very popular, while my views are considered to be old-
fashioned.
I t may also be here stated th at the inclusion of a species in the
‘ Hand-list j does not necessarily imply th at I personally vouch for its
distinctness. I have not had the time to enquire into the claims
of every species there mentioned. My efforts have been directed to
enumerating the names of all such as have been described since the
publication of the | Catalogue of Birds,’ so as to bring the subject up
to d a te ; and in this respect I tru s t that some useful work has been
accompli.shed.
I f the present ‘ Hand-list ’ has any pretension to completeness, this
will be in a great measure due to the co-operation of the many friends
who have allowed me to send them proofs as it proceeded, and the work
has, therefore, somewhat of an international character.
• I beg to return my sincere thanks to the following gentlemen, who
have rendered me their help and advice.
Great Britain.-—Dr. P. L. Sclater; the Hon. Walter Rothschild,
D.Sc., M.P. ; Dr. Ernst H a rte rt; Mr. W. R. Ogilvie-Grant;
Dr. C. W. Andrews, P .R .S .; Mr. W. P. P y c ra ft; Mr. Charles
Chubb ; Mr. G. M. Mathews.
Germany.—Prof. Dr. Reich enow; Count von Berlepsch; Dr. Carl
Hellmayr; Dr. A. B. M ey er; Dr. Otto P in sch ; Pastor
Kleinschmidt.
Russia.—Dr. Bianchi.
Ita ly .—Count Salvadori.
America.—Mr. Robert Ridgway; Dr. L. Stejneger; Prof. J.
A. A llen ; Mr. C. W. Richmond; Mr. Harry Oberholser:
Mr. Witmer S to n e ; Mr. P. M. Chapman; and Mr. Outram
Bangs.
Australia.—Mr. A. J . N o r th ; Mr. A. G. Campbell.
I also received great assistance from my friends the late Mr. Howard
Saunders and the late Prof. Dr. Oustalet.
In any future edition of the •• Hand-list ’ I should divide the Class
Aves into the two Sub-Classes, Palceognathce and Neognathce, since I
consider this arrangement, proposed by Mr. Pycraft, more natural than
the old division into Ratitce and Oarinatce.
I t will be of interest to tabulate the number of species of Birds, fossil
and recent, now known to science, and the following is an attempt to
arrive at something like an estimate. I have been a t some trouble to
make this computation, which I believe to be fairly complete, but a t the
time of writing, the ‘ Zoological Record ’ for 1908 has not yet been
printed, and I may not have included some of the species described
in recent years. The same can be said of those described during the
present year, 19Q9 ; but the totals may be considered fairly accurate,
and we may conclude th at the number of known species of birds is about
18,937, distributed under 2810 genera.
Iu ‘The Ibis ’ for January 1900 (p. 215) the Editors gave an estimate
of the number of genera and species enumerated in the first volume of
the ‘ Hand-list ’ as follows : —
Genera 851; Species 3727.
Sir Ray Lankester, in his “ Preface” to Yol. I I . (June 1900), gives a
slightly smaller estimate:-^
Genera 830 ; Species 3626.
The Editors of ‘ The Ib is ’ have probably included additional species
which, to their knowledge, had been described since the publication of
Vol. I. of the ‘ H and-list.’
My present computation for Vol. I. is as follows :—
Genera 865 ; Species 4261,