110 ON THE STRUCTURES AND DISTRIBUTION OF THE 



trachia, Pleurodire Tgrtoises, its Elapid venomous snakes, and the whole Flora, 

 according to Unger. 



R. Ne ot rop ica.— Marsupial and Edentate Mammalia, Inferior Rodentia and 

 Quadrumana, Pleurodire Tortoises, Pleurodont Lacertilia, Arciferous Batrachia, 

 Claraatorial and Pullastriform Birds, Characin and Erythrinid Malacopterigii. 



R. Ne a re tic a. — Lacking most of the inferior tjrpes of the preceding, it retains 

 more Arcifera and Bufoniformia, Pleurodont Lacertilia, and Clamatores, than 

 the following ;, possesses the inferior Urodela, the Aphredoderus and Percopsis, 

 and wants as types of the 



R. Palae arctica. — Higher Urodela, Acrodont Lacertilia, higher Gallinte* and 

 Oscines. This is inferior, however, to the last in Ophidia Solenoglypha. 



R. Palaeotropicaor Indica, — Superior in ty|)es of Teleostei, Batrachia Anura, 

 Lacertilia Acrodonta, Testudinata,t Gallinaceous and Oscine Aves, Mammalia, 

 including Homo. ■ 



If the above succession be marked out in present time, it has no doubt existed 

 throughout a longer or more probably shorter series of recent geologic periods or 

 epochs, and over areas of course only partially coinciding with those of the present 

 Regions. This points to the Regio Palasotropica, faunally and fiorally most advanced 

 in time, as the seat of first origin of the human species, as already indicated by revela- 

 tion and tradition. The fact of its being the source of such a majority of the vegeta- 

 ble and animal products most useful to the species, is in harmony with this view j 

 and more so is the known, almost regular departure from the typical symmetry of 

 form and expression of mind by body, in the men of the dilFerent Regions. That these 

 areas were occupied by man in this succession, determined by their preparation for 

 maintaining a degree of developmental perfection, sufficient to enable him to take his 

 part in " the struggle for existence," is a natural sequence of the relation in time. 



Paleontology is as yet too incomplete to answer the question as to how ancient 

 such a relation may be. Its indications are quite contradictory, and perhaps may 

 not be relevant, prior to Csenozoic time. 



Thus the resemblance between existing Australian and American types and terti- 

 ary European! forms successively, harmonizes with the existent relations between 

 the faunse here proposed ; but the similarity between fresh water shells of the Upper 

 Missouri Lignite and recent Indian forms, between American Eocene and European 



* B. g., Phasianus, Tetrao, Lyrurus, Tetraogallus, etc. 



t Possesses a greater number of distinct types of Emydidae and Testudiaidae than the K. Nearctica, though 

 not much beyond it. 



X Among others, the extinct genera Polysemia Myr. and HeUarchou 3Ii/r. exhibit the unossified carpus and 

 tarsus of the recent American Plethodontidse. 



