THV. n 



GYMNOSPERMAE 



599 



Dammara yield Kauri Copal but no Dammar Resin ; Araucaria brasiliana and A. 

 imbricata are stately S. American forest trees. The genus Sequoia includes the 

 most gigantic trees known ; specimens of S. gigantea from the Californian Sierra 

 Nevada attain a height of 100 m. and a diameter of 12 m. The beautiful 

 S. sempervirens from the coastal mountains is hardly inferior in size. 



The Silver Fir (Abies pectinata, Fig. 590 A -C] is a native of the mountains of 

 the middle and south of Europe. It bears only long shoots. The flat, needle-like 

 leaves, marked below by two white lines and emarginate at the tip, are borne on all 



FIG. o'.'l. Ficea excelsa (\ nat. size). 1, Twig with male flowers. J. Terminal female flower. 3, 

 Pendulous cone. k. Microsporophyll. 5, Macros porophyll ; the bract-scale is covered by the 

 large, bent-back, ovuliferous scale ; an ovule is visible at the base of the ovuliferous scale. 

 6, Ripe seed with the wing funned by a detached portion of the ovuliferous scale, (x 4-6.) 



sides of the axis, but are twisted into a horizontal position on the branches 

 illuminated from above. They live for 6-8 or even for 15 years. The male 

 flowers stand in the leaf-axils on the under side or on the flanks of the shoot, 

 and grow downwards so that the pollen-sacs are directed upwards. The wall of 

 the sporangium opens by an obliquely longitudinal split, which gapes widely and 

 allows the winged microstores to escape. The female flowers arise from the 

 upper side of a b*ranch and are directed vertically upwards. The bract-scales 

 are longer than the broad, ovuliferous scales. The fertilised cones retain the 

 upright position, and when ripe the scales separate from the axis and so set the 

 seeds free from the plant. The development of the seeds takes a year. Abies 



2 Q 2 



