46 INTRODUCTORY EXPLANATIONS. 



2. The English Type. — The plants of this geographic 

 type are distinguished from those of the British type by 

 having their chief prevalence in England, and particularly 

 in its more southern provinces ; whence they gradually 

 become rare in a northern direction, and finally (with few 

 peculiar exceptions) find an earlier northern limit or ces- 

 sation than those of the preceding type. Their terminal 

 lines are very different among themselves; some of the 

 species being entirely limited to two or three of the most 

 southern provinces of England ; while other species occur 

 in all the provinces of Britain, with an exception of two 

 or three of the most northern; the great majority having 

 their limits between these two extremes. Those species 

 which extend into nearly all the provinces, except two or 

 three of the northern, approximate very closely to the less 

 general examples of the British type ; and, in fact, there 

 are cases where it becomes almost optional whether the 

 species are to be referred to the one or to the other type. 

 To the characters of diminished frequency and earlier 

 northern termination, which distinguish the species of the 

 English from those of the British type, must be added that 

 of spreading into both the eastern and the western pro- 

 vinces of England, and without any very striking diffe- 

 rence of comparative frequency towards the two sides of 

 the island, beyond that which may be caused by the re- 

 pellent influence of the western mountains, which neces- 

 sarily tend to banish such species as are naturally 

 adapted to low situations, in a warmer and drier climate 

 than that of our mountainous tracts. The name of 'Eng- 

 lish Type ' will not be misunderstood to indicate that all 

 the species are peculiar to England, but is to be under- 

 stood only as implying that the species are apparently 

 adapted to the climate of England, either being restricted 

 to that part of Britain, or being more prevalent there than 



