The Palaearctic and the Nearctic. But to justify such a division it is necessary to establish either an exclusive possession or a marked predominance of types in the one which are correspondingly deficient in the other.
To take, for example, one of the most characteristic features of the Palaearctic region, its catkin-bearing glpridiini,c frpec ~,, North Amnt4ra ~ fnA nrnrgar~, the came a-pliers as in the Old Worldoaks, chestnuts, beeches, hazels, hornbeams, birches, alders, willows and poplars.
Thus comparing the Nearctic and Palaearctic floras we find striking differences overlying the points of agreement already indicated.
They are six in number: (1) Palaearctic, including Europe, Asia north of the Himalaya, and Africa north of the Sahara; (2) Ethiopian, consisting of Africa south of the Atlas range, and Madagascar; (3) Oriental, including India, Indo-China and the Malay Archipelago north of Wallace's line, which runs between Bali and Lombok; (4) Australian, including Australia, New Zealand, New Guinea and Pol y nesia; (5) Nearctic or North America, north of Mexico; and (6) Neotropical or South America.
In some cases, such as the Ethiopian and Neotropical and the Palaearctic and Nearctic regions, the faunas, although distinct, are related, several forms on opposite sides of the Atlantic being analogous, e.g.
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