42 THE GEOGRAPHY OF PLANTS. 



not produce ripe fruit, and the winter is so 

 mild that the myrtle, camellia, and other green- 

 house plants, grow luxuriantly in the open air 

 all the year round. In the northern hemi- 

 sphere of the globe, all the eastern coasts of 

 continents and islands are colder than the 

 western coasts of the same latitudes. This is 

 confirmed by repeated observations, though we 

 cannot tell why. Ireland, England, and Bel- 

 gium, have the same isothermal line, but on 

 the eastern coast of Asia it passes just above 

 Pekin, in China, which is 12 nearer the 

 equator. Pekin has the same parallel of lati- 

 tude with the south of Italy and Toledo, in 

 Spain, where the orange flourishes, and many a 

 tropical plant ; but at Pekin, the winter's cold 

 is far greater than in Great Britain, and falls 

 short by only two or three degrees of that at 

 North Cape. Canada is further south than 

 Paris, yet it shows the temperature of Droii- 

 theim, in Norway. The trees which grow at 

 New York, in the latitude of Naples, flower at 

 the same time as they do at Upsal. Norway, 

 exposed to the moist and temperate atmosphere 

 of the ocean, enjoys a singularly mild winter, 

 but receives very little of the sun's rays in 

 summer. Lapland has a colder winter, but a 

 warmer summer ; and, accordingly, it is found 

 that such plants as require only a few weeks of 

 warm weather to bring them to perfection, 

 succeed in Lapland, though they will not grow 

 in Norway ; while those which are easily killed 

 by severe frost, flourish better in Norway than 



