SECT. 11 PHANEROGAMIA 539 



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

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

 illuminated from above. 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 microspores to escape. The 

 female flowers arise from the upper side of a branch 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 Nordmanniana from the Caucasus, A. ]}insapo from Spain, 

 A. concolor, A. halsumea, and A. nohilis from N". America are in cultivation. 



Picea excelsa, the Fir (Fig. 509), is a fine tree of pyramidal shape ; it has 

 no short shoots, and the long shoots bear on all sides pointed, quadrangular, 

 needle-shajjed leaves, which on horizontal or pendulous branches stand more 

 or less erect. Male flowers as a rule on shoots of the previous year ; on flowering 

 they become twisted into an erect position. The two pollen-sacs open by a 

 longitudinal slit. Female flowers terminal on the shoots of the previous 

 year usually near the summit of the tree. They stand erect at the time of 

 flowering. The ripe cones are pendulous and, after setting the seeds free from 

 between the scales, fall in pieces. The development of the seeds is completed in 

 one year. The male and female flowers occur on the same individual. Picea 

 orientalis from Asia Minor and Picea alha from N. America are frequently 

 cultivated. 



Larix europaea, the Larch, is one of the few deciduous Conifers and rejalaces its 

 foliage annually. There is a diff'erentiation into long and short shoots. The 

 former bear the narrow linear leaves on all sides and continue the branching of the 

 pyramidal tree, the lower branches of which often droop downwards. The sliort 

 shoots arise in the axils of the leaves of the long shoots of the preceding year, 

 and bear a rosette of 30-40 leaves which are somewhat shorter but resemble those 

 of the long shoots. The flowers occur in a position corresponding to that of the 

 short shoots. The male flowers are bent downwards when fully developed, and 

 the opening of the upwardly directed pollen-sacs occurs as in Abies. The erect 

 female cones produce seed in the same year. 



The most advanced difl'erentiation of the vegetative organs is found in the 

 genus Pinus ; P. silvcstris, the Scotch Fir, will serve as an example (Fig. 510). 

 Young seedlings in the first or second year have long shoots bearing needle-shaped 

 leaves. On older plants this type of foliage is lost ; the needles are replaced by 

 colourless, membranous scale-leaves in the axils of which stand the short shoots. 

 These have 2 — in other species 3 or 5 — needle-shaped foliage leaves. The latter 

 are about 5 cm. in length, their flat surfaces are turned to face one another, and the 

 outer or lower surface is convex. The growing points of the short shoots soon 

 become functionless unless stimulated to activity by the death of the apical bud. 

 The male flowers appear in large numbers at the base of the long shoots of the 

 current year and stand in place of the short shoots. One or several female flowers 

 arise at the tip of similar long shoots, and each corresponds in position to a shoot 

 of unlimited growth. At the time of flowering they are erect, but are bent down- 

 wards after pollination. The seeds ripen in the second year, and are set free by 

 the separation of tlie scales of the cone, which till then have been closely pressed 

 together. The cones subsequently are shed (Fig. 510). Pinus moniana, a dwarf 

 Pine occurring on mountains ; P. pinea, P. cembra, with edible seeds ; P. laricio, 



