CHAP. iTi ZOOLOGICAL REGIONS 51 



If, however, we compare the number of species, which are 

 common to the Nearctic and Palasarctic regions with the 

 number common to the western and eastern extremities of 

 the latter region, we shall find a wonderful difference 

 between the two cases ; and if we further call to mind the 

 number of important groups characteristic of the one 

 region but absent from the other, we shall be obliged to 

 admit that the relation that undoubtedly exists between 

 the faunas of North America and Europe is of a very 

 distinct nature from that which connects together 

 Western Europe and North-eastern Asia in the bonds of 

 zoological unity. 



Definition and Characteristic Groups of the Neotropical 

 Region. — The Neotropical region requires very little defi- 

 nition, since it comprises the whole of America south of 

 the Nearctic region, with the addition of the Antilles or 

 West Indian Islands. Its zoological peculiarities are almost 

 as marked as those of Australia, which, however, it far ex- 

 ceeds in the extreme richness and variety of all its forms 

 of life. To show how distinct it is from all the other regions 

 of the globe, we need only enumerate some of the best known 

 and more conspicuous of the animal forms which are pecu- 

 liar to it. Such are, among mammalia — the prehensile- 

 tailed monkeys and the marmosets, the blood-sucking bats, 

 the coati-mundis, the peccaries, the llamas and alpacas, the 

 chinchillas, the agoutis, the sloths, the armadillos, and the 

 ant-eaters ; a series of types more varied, and more distinct 

 from those of the rest of the world than any other conti- 

 nent can boast of. Among birds we have the charming 

 sugar-birds, forming the family Coerebidsa ; the immense 

 and wonderfully varied group of tanagers ; the exquisite 

 little manakins, and the gorgeously-coloured chatterers ; 

 the host of tree-creepers of the family Dendrocolaptida3 ; 

 the wonderful toucans ; the pufF-birds, jacamars, todies and 

 motmots ; the marvellous assemblage of four hundred dis- 

 tinct kinds of humming-birds ; the gorgeous macaws ; the 

 curassows, the trumpeters, and the sun-bitterns. Here again 

 there is no other continent or region that can produce such 

 an assemblage of remarkable and perfectly distinct groups 

 of birds ; and no less wonderful is its richness in species, 

 since these fully equal, if they do not surpass, those of the 



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