GEOGRAPHICAL DISTRIBUTION 313 



however, troubling ourselves on that score, or attempting a com- 

 plete history of the subject since his treatment of it, it is proper to 

 remark that Prof. Huxley pointed out {Proc. Zoo]. Sac. 1868, pp. 

 313-ol9)that there was reason to divide the earth's surface lati- 

 tudinall}-, rather than longitudinally as Mr. Sclater had done, and 

 that jour primary Regions were better than m: — these four being : I. 

 Ardogsea, comprising Mr. 8clater's Indian, Ethiopian, Palaearctic, 

 and Nearctic Eegions : II. Austro-Colmnbia, corresponding Avith the 

 Neotropical Region ; III. Audralasia ; and IV. New Zealand — this 

 last being ctit ofT from that gentleman's Australian Region. Eight 

 years later, Mr. Wallace in his great work,^ for which zoologists 

 can never be too thankful, disregarding Prof. Huxley's scheme, 

 adopted with some very slight modifications the plans of Mr. 

 Sclater, Avhich had been already followed in the main by many 

 others, and among them by the present AAi'iter in a contribution 

 to the Encydopsedia Britannica. In the coui'se, however, of com- 

 piling that contribtition a considerable number of doubts arose in 

 his mind. Some of them he at the time intimated ; but it was not 

 until several years after that he saw how the chief est of them should 

 be dispelled. The full force of Prof. Huxley's reasoning is now 

 evident to him, and he has to m-ge the recognition of New Zealand 

 as a primary division, Avhile the recent ornithological investigation 

 of Alaska, sheAving that it is peopled in summer by so many Fasseres 

 hitherto supposed to be of purely PakTearctic type, has convinced 

 him that Prof. Huxlev's statement of the Nearctic area being far 

 more nearly allied to the Paltearctic than to the Neotropical 

 Region is not only true but has a still deeper meaning, for that it 

 is impossible justifiably to separate the Paltearctic and Nearctic 

 areas as "Regions," though we may keep the epithets as con- 

 veniently indicating geographical portions of one enormous but 

 continuous Region, to which the name Holardic may be fitly 

 applied.- Some rectification of the hitherto -accepted frontier of 

 the Neotropical Region may thereby be recjuired, but that is a 

 comparatively unimportant consideration, and it is not proposed 



1 The Geographical Distribution of Animals. 2 vols. London : 1876. j\I\- 

 own gratitude to the author for allowing me at a critical time to see the manu- 

 script of this work prior to its publication has been before expressed {ETicydo'p. 

 Brit. ed. 9, iii. p. 737) ; but will never be forgotten. 



- I have to thank Prof. Heilprin, who had originally {Proc. Ac. Philad. 



1882, p, 334) bestowed the name " Triarctic " on this combination, for so readily 

 adopting (i\'7n<U7-e, xxvii. p. 606) my suggestion to call it "Holarctic," under 

 which name it appears in the excellent defence of his position {Proc. Ac. Philad. 



1883, pp. 266-275) as well as in his work (IVte Geographical and Geologicat 

 Distribution of Animals. New York : 1887). The objections raised to this 

 combination by Mr. Wallace and Dr. Gill will be found in Nature (xxvii. 

 p. 482, xxviii. ].. 124). 



