FOLIATION. 25 



vfir. Loiciana and in A. t/randis the leaves on the barren branches 

 spread away from either side of the axis markedly in one plane, whilst 

 those on the cone-bearing branches are much shorter and curve inwards 

 like those of the Colorado type (A. concolor). Another peculiarity observable 

 in the leaves of Abies is that those on the latest growths of the 

 principal axis (leader shoot) are in most species much smaller and more 

 distant than those on the branches, and never assume the pseudo- 

 distichous arrangement. 



In Cryptomeria, Sequoia r/igantea, the Araucarias included in the 

 section Eutassa, and many Junipers, the adult leaves are awl-shaped 



Fig. 10. Quinate leaves of Pimis Strobus. 



(subulate) or some slight modification of that form, and often falcately 

 curved. In Taxodium, the Redwood, the Yew and other Taxads they 

 are linear, flattened, and pointed at the apex (in Torreya spine-tipped). 

 In the Cypress and its allies (Cupressinese) the leaves are often hetero- 

 morphic, that is to say, they occur in two, three or even more different 

 forms; primordial leaves are often produced simultaneously with adult 

 leaves, the former being always linear or acicular and more or less 

 spreading, whilst the latter are scale-like, often in two different forms, 



