GEOGRAPHICAL DISTRIBUTION OF PLANTS. 



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Indian flora. The Scitaminece are here much more numerous than in America, as well as 

 the Leguminosce, such as pease and broom. The Cucurbitacece, or the cucumber tribe, and 

 T&acece, or the lime-tree tribe, are also abundant, but in a less degree. The region com- 

 prehends India east and west of the Ganges ; the islands of Madagascar, Bourbon, and 

 Mauritius ; those between India and New Holland ; and perhaps the tropical part of this 

 last continent. 



19. The mountains of India form one or two regions, the vegetation of which differs 

 from that of the plains. These countries perhaps constitute one region with nearly the 

 whole of Central Asia. 



20. The floras of Cochin China, Tonquin, and the south of China, notwithstanding 

 their resemblance to that of India, present a sufficient number of peculiar indigenous 

 plants to constitute a distinct region. 



21. The flora of Arabia, Persia, differing from that of India and the Mediterranean, 

 forms a particular botanical region, characterised by the numerous species of Cassia and 

 Mimosa. Of the latter family, there is the beautiful acacia of Lalla Rookh : 



" Our rocks are rough ; but smiling there 

 Th' acacia waves her yellow hair, 

 Lonely and sweet, nor lov'd the less 

 For flow'ring in a wilderness." 



It is probable that Nubia and part of Central Asia belong to the same region ; and Abys- 

 sinia, the elevated parts of which possess such a different climate, may form one of the 

 great subdivisions, or even a totally distinct region. 



22. The islands of the South Sea, which lie within the tropics, form a separate 

 region, but with a slender degree of peculiarity. Among 214 genera, 173 are found in 

 India, and most of the remainder are in common with America. The bread-fruit tree is 

 among the characteristics of these islands, although it is not confined to them. 



To the preceding enumeration there should be added- those islands which have a dis- 

 tinct vegetation, as Kerguelen's Land, or the Island of Desolation, the whole flora of 

 which, when visited by Captain Cook, consisted of sixteen or eighteen species, all of 

 which were considered to be peculiar to it. St. Helena is another example, characterised 

 by an indigenous vegetation, not a single species of which is found on the continent of 

 Africa, while not more than two or three of its species occurs on the continent of 

 America. 



It thus appears, upon examining different and distant localities, that each has a vege- 

 tation peculiar to itself, while a common analogy prevails among them, where the physical 

 conditions of soil, temperature, and local circumstances are the same. Plants of the 

 simplest structure, or the cryptogamic tribes the lowest orders in the vegetable creation 

 are the most extensively diffused, the same species existing in far remote countries. 

 Of the lichens observed in New Holland, two thirds are also natives of Europe ; and of 

 the one hundred species of ferns discovered there, twenty-eight are common to other 

 countries. It is -very different with plants of the more perfect kind, or the dicotyledonous 

 tribes, the aggregate number of which, known to Mr. Brown in New Holland, amounts to 

 2100 species, of which only fifteen, or about the one hundred and ninety -third part, are 

 found in Europe. Of the plants belonging to an intermediate class, or the monocotyledo- 

 nous tribes, amounting to 860 species, there are thirty, or about the one. twenty-ninth 

 part, chiefly grasses, that are native to Europe. " If the animal kingdom in New Hol- 

 land," says M. Leschenault, " offers remarkable peculiarities which isolate it from all 

 other parts of the world, the vegetable kingdom has a character no less distinctive. This 

 character relates not only to botanical differences, but likewise to a natural physiognomy 

 which would be remarked by the most careless observers. The vegetation only of the 



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