316 PROF. HUXLEY ON THE ALECTOROMORPH^. [May 14, 



making it a mere subdivision of the Old World. Exclusively con- 

 fined to it are the 



DromceideB, Strigopince, 



Dhiormthidce, Plictolopkin(e, 



Ap tenjgida , Trichoglossince, 



Bidunculidce, Menuridce. 

 Dididce, 



Like Austro-Columbia it aboiuids in Parrakeets and Pigeons ; but 

 Woodpeckers are entirely absent, and only a few Cuckoos represent 

 the Pair-toed Coccygomorphce. 



Positively, this region is characterized by the abundance of Mar- 

 supials (except Opossums) over a large part of its area, by the pre- 

 sence of Monotremes iu a small part ; negatively, by the absence of 

 almost all other terrestrial Mammals. 



In fact the population of this great region (which 1 should prefer 

 to call "Australasia") is so very different not only from that of 

 Arctogsea, but from that of Austro-Columbia, that a good case might 

 be made out for regarding it as a primary division in zoogeography, 

 of the same value as Arctogsea and Austro-Columbia. Indeed 1 am 

 not disposed to weigh lightly the claims of the New-Zealand islands 

 to a similar distinction. This region of the world alone possesses 

 two families of Ratitce which are exclusively confined to itself. 

 The AlectoromnrphcR are represented only by a Quail. Again, in 

 the absence of all Ophidia and Chelonia, and of all terrestrial Mam- 

 malia with the doubtful exception of a Rodent or two. New Zealand 

 is without a parallel in lands of its size. 



If this view were admitted, it would be requisite to divide the 

 earth's surface, for the purpose of geographical zoology, into four 

 primary regions : — I. Arctogsea. II. Austro-Columbia. III. Aus- 

 tralasia. IV. New Zealand. But this arrangement would leave 

 out of sight the important fact that in some respects the three latter 

 are less unlike one another than they are unhke the first — for 

 example, in the paucity or absence of Ungulate Mammals, the 

 abundance of Edentates and Marsupials among JNIammals ; and, in 

 the class of Birds, nothing can be more remarkable than the great 

 development of the Psittacomojphce in both Australasia and Austro- 

 Columbia, while they are, comparatively, so feebly represented iu 

 India and South Africa, and are absent, save a stray species or two, 

 in North America*. Not only in this circumstance, but in the 

 wonderful uniformity of their osteology, the Psittaco)iwrphce-\ nearly 

 repeat the phenomena presented by the Peristopodes, and helj), with 

 them and the three-toed Ratitce, to bind together the widely sepa- 



* Tlie PeristeromorphcB resemble the Parrots in theii- remarkable development 

 in Australasia and Austro-Columbia, and in their comparative paucity in India 

 and Africa. But the conti-ast is less marked ; and they extend over all the tem- 

 perate portions of Arctoga?a. See Wallace "On the Pigeons of the Malav 

 Archipelago" (Ibis, 18(5.5, p. 3Go). 



t See Wallace, " On tlie Parrots of the Malayan Kegion " (Proc. Zool. Soc. 

 18<>4. p. '2.T2). and Finsch, 'Die Papagcien." 



