206 GEOGEAPHICAL SITUATION OF PLANTS. 



quantity of water sufficient for a draught to a tlairsty person ; the end of the leaf 

 forms a lid, as if "to prevent the evaporation of the fluid. Various other plants, 

 in hot regions, furnish refreshing draughts or cooling fruits for the thirsty traveler. 

 These remarks might be pursued to an extent as great as the vastness of the vege- 

 table kingdom and the \v%nts of man ; we have merely glanced at the subject of 

 the adaptation of plants to the wimts of animal life, hoping that these few sugges- 

 tions may lead the student to trace, from observation of the works of nature, the 

 operations of that great designing Mind which rules and governs all with infinite 

 wisdom and benevolence. 



316. We find the eartli to be covered witli a multitude ol 

 species of plants, differing not more by their external forms 

 than by their internal structure, and each endowed with pecu- 

 liar habits and instincts. Some species seem adapted to the 

 mountains, some to the valleys, and others to the plains ; some 

 require an argillaceous or clayey soil ; others a calcareous soil, 

 or one impregnated with Iwie / others a quartzose or sanely soil ; 

 and some will only grow where the earth contains soda or ma- 

 rine salts. Many plants will grow only in water ; we find here 

 such as are peculiar to the marsh, the lake, the river, and the 

 sea. 3Iany plants require a very elevated temperature ; some 

 will grow only in mild and temperate climates, and others only 

 in the midst of frost and snows. Thus every country v^here 

 man is to be found has its vegetation. 



317. Some species, with respect to localities are confined to 

 narrow limits. A species of Origanum (the TouTnefortii) was 

 discovered by Tournefort, in lYOO, upon one single rock in the 

 little island of Amorgos, in the Greek Archipelago ; eighty 

 years al\erward the plant was found in the same island, and 

 upon the same rock, and has never been discovered in any 

 other situation. Borne ])lant8 confine themselves icitliin certain 

 longitudes^ scarcely varying to the right or left. The Menziesia 

 •pallifolia^ a species of heath, confined between ten and fifteen 

 degrees of west longitude, is found in Portugal, Spain, and Ire- 

 land. Latitude and elevation^ by reason of mountains and 

 table-lands, produce a greater variety in the appearance of 

 vegetation than almost any other causes. Feio ])lants are found 

 to endure extreme cold. Botanists formerly estimated, that at 

 Spitsbergen, in north latitude 80°, there were but about thirty 

 species of phenogamous plants ; in Lapland, T0° north latitude, 

 five hundred and thirty-nine species ; at Madagascar at the 

 tropic of Capricorn, five thousand ; and at the equator a much 

 greater number. These estimates fall very far short of the 

 number of species now known, but they may give some idea of 

 the difierence in the vegetation of cold and warm climates. 



318. Geograjyhiccd Situation of Plants. — Every country ex- 

 hibits a botanical character pecidiar to itself. Linnaeus, in his 



Reflection.— 316. Plants adapted to various soils, &c.— 317. Locality— Extreme sold.— 318. Every 

 countrv has its own botanical character. 



