THE WELLINGTONIA 131 



of the. best represented types in the far off epoch 

 when our OoHte limestones were being deposited. 

 The remarlcable Maidenhair tree of Japan is the sole 

 living type of another Order ; whilst the marvellous 

 Tumbo'a of Angola, better known as -Welwit'schia 

 mira'bilis, is one of the few members of a third. 

 Three-fifths of the existing Gymnosperms, however, 

 belong to the Order Goniferce. 



The Goniferce have a primary root which persists 

 as a well-developed tap-root, giving them the firm hold 

 on the ground which enables them to grow to a great 

 height, and to support a mass of evergreen foliage 

 without being blown over. The most gigantic mem- 

 bers of the gr-o«p, the genus Sequoia, have also 

 strong secondary roots, which spread near the sur- 

 face of the ground ; but require a very deep alluviaL 

 soil for their most perfect development. 



The most obvious character of most Coniferous 

 trees is the straight, tapering stem or "leader," 

 growing generally fast, and of a bulk far exceeding 

 any of its branches, the whole tree assuming the 

 outUne of a pyramid or cone, narrow at the base in 

 proportion to its height. But if the trees are crowded 

 together when young, the lower branches, deprived of 

 light and air, die off, leaving traces of their existence 

 as " knots " in the wood of the stem ; and the trunk, 

 no longer nourished by branches near its base, in- 

 creases more in diameter in its upper portion, and. 

 thus becomes more cylindrical. This is strikingly 

 illustrated in the difference between the stem of the 

 Wellingtonia, as we commonly see it in this country, 

 clothed with branches to the ground, and that of the 



