Bevieios and Notices of Boohs. 



129 



adapted for an excessive climate, and therefore tlirive best on con- 

 tinents ; the latter for an equable one, and consequently succeed 

 most upon islands. 



" It may also be remarked, that annuals are adapted for con- 

 tinental climates, as they require heat for the ripening of their 

 seeds, but die away in winter; whilst perennials are better calcu- 

 lated for islands, as it is essential that the winter should not be so 

 rigorous as to destroy them, but not equally necessary that the 

 summers should be always hot enough to ripen their seeds, a fail- 

 ure in this respect for several successive years not entailing the 

 destruction of the species." 



Here the extreme temperatures of a country, as distinguished 

 from the mean temperature both of its seasons and its year, must 

 be carefully kept in view. For that which determines the flora of 

 a country, or the plants which will thrive and live in its climate, is 

 not whether the plants will live through such winters as ordinarily 

 occur, but whether they will survive the severest frosts that have 

 happened, and may therefore be expected to recur in a succession 

 of years. But the number of species which admit of cultivation 

 is greater than that of those which grow wild, inasmuch as the 

 former can be maintained by the art of man protecting them 

 during winter, or replacing them with new plants when the old 

 ones happen to be destroyed by frost. This is particularly the 

 case with those whose cultivation is remunerative. As man has 

 little or no power to change the climate, it is only by studying 

 the climate of his neighbourhood in all its details that he can 

 take every advantage of it, and thus rise superior to it, and in 

 some sense overcome it. The subject of local climate is one de- 

 serving more attention than it has yet received. The exposure of 

 a piece of ground, its sloping or level character, its relatively low 

 or high position, the nature of its subsoil or its drainage, its shel- 

 tered or exposed situation, and its relation to moisture or dryness, 

 may all conspire to give it as mild and genial a climate as is 

 enjoyed some degrees southward. 



We conclude this notice with the following extract, showing 

 the effect different seasons have on agricultural produce : — 



" It may be useful for the farmer to possess the data for esti- 

 mating the influence which a summer, warmer or colder, wetter 

 or drier than ordinary, has exerted upon the production of his 

 farm, so as not to be misled in his calculations as to the advan- 

 tages or disadvantages of any novel plan of cultivation. 



" These data have in part been supplied by Mr Lawes in an 

 elaborate paper published in the eighth volume of the Royal Agri- 

 cultural Society's Journal for 1848, in which he shows, that in 

 1844, 1845, and 1846, the difference in the amount of produce was 

 in accordance with the general character of their respective seasons. 



NEW SERIES. VOL. XJX. NO. I. JANUARY 1864. R 



