GEOGRAPHICAL DISTRIBUTION OF ANIMALS. 



the deciduous trees, coincides, in general, with the limit of the 

 pines, it may be said that the cold region of the temperate 

 fauna extends as far as the pines. In the United States this 

 coincidence is riot so marked as in other regions, inasmuch as 

 the pines along the Atlantic coast extend into Florida, while 

 they do not prevail in the Western States ; but we may con- 

 sider as belonging to the southern portion of the temperate 

 region, that part of the country south of the latitude where 

 the palmetto or cabbage-tree (Chamaerops) commences, namely, 

 all the States to the south of North Carolina ; while the 

 States to the north of this limit belong to the northern portion 

 of the temperate region. 



609. This division into two zones is supported by obser- 

 vations made on the maritime faunas of the Atlantic coast. 

 The line of separation between them, however, being influ- 

 enced by the Gulf Stream, is considerably farther to the north ; 

 namely, at Cape Cod : although there is also another decided 

 limitation of the marine animals at a point nearly coinciding 

 with the line of demarcation above-mentioned, namely, at 

 Cape Hatteras. It has been observed, that of one hun- 

 dred and ninety-seven mollusca inhabiting the coast o^ 

 New England, fifty do not pass to the north of Cape Cod, 

 and eighty- three do not pass to the south of it ; only sixty-foui- 

 being common to both sides of the Cape. A similar limita- 

 tion of the range of fishes has been noticed by Dr. Storer ; 

 and Dr. Holbrook has found the fishes of South Carolina to 

 be diiferent from those of Florida and the West Indies. In 

 Europe, the northern part of the temperate region extends to 

 the Pyrenees and the Alps ; and its southern portion consists 

 of the basin of the Mediterranean, together with the northern 

 part of Africa, as far as the desert of Sahara. 



610. A peculiar characteristic of the faunas of the tem- 

 perate regions in the northern hemisphere, when contrasted 

 with those of the southern, is the great similarity of the pre- 

 vailing types on both continents. Notwithstanding the im- 

 mense extent of country embraced, the same stamp is every- 

 where exhibited. Generally, the same families, frequently 

 the same genera, represented by diiferent species, are found. 

 There are even a few species of terrestrial animals regarded 

 as identical on the continents of Europe and America ; but 

 their supposed number is constantly diminished, as more 

 accurate observations are made. The predominant types 



