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FO UR TH GR UP. — SEED- PL A NTS. 



species. The leaves of the Podocarpeae and of Dammar a are broader and flat, and the 

 broad flat stalked leaves of Gingko are even two-lobed with a deep indentation at the 

 apex as if from dichotomous division. It is not unfrequently the case, especially in the 

 Cupressineae, that the foliage-leaves of the elongated primary axis are diff'erent in 

 form from those of the same axis at a greater height and from those of the lateral 

 shoots ; the former, in Thuja for example, Juniperus virginiana or Cupressus and 

 others, stand out clear from the branch and are acicular and of a fair size, the latter 

 are very small and closely applied to the axis ; these earlier leaves sometimes make 

 their appearance on single branches of full-grown plants. The axis of the shoot 

 inside the bud is so densely clothed with the basis of the leaves, that no free portion 

 of the axis can be seen between them ; and when the bud unfolds and the axis 

 elongates considerably, stiU the basis of the leaves usually grow to such an extent in 

 length and breadth, that they spread over the surface of the elongated shoot and 

 conceal it beneath a green covering, in the areolate markings on which it is easy to 

 distinguish the parts which belong to the separate leaves ; this is very distinctly the 

 case in the Araucarieae, and in many species of Pinus, but is not uncommon in other 

 genera; in Thuja, Cupressus, Libocedrus, and some others, the axis of the shoots is 

 in like manner entirely concealed by these leaf-cushions, while the free portions of 

 the leaf are very small and are often only short projecting points or prominences. 

 The phyllotaxis in the Abietineae, Taxineae, Araucarieae, Podocarpeae, and other 

 groups is spiral; the Cupressineae form whorls which have usually from three to 

 five members immediately above the cotyledons, but a smaller number at a greater 

 height on the primary axis, while the lateral axes generally begin at once with 

 decussate pairs of leaves, which in the bilateral shoots of Callitris and Libocedrus are 

 alternately larger and smaller ; m Juniperus and Frenela the whorls of the lateral axes 

 as well have from three to five members and are alternate ; the pairs of leaves in 

 Dammara intersect each other at an acute angle. The foliage-leaves of most 

 Conifereae are very persistent and may be many years old, their bases increasing in 

 size for a long time with the increase in the circumference of the axis ; the leaves are 

 deciduous in Lan'x and Gingko, in Tax odium distichum the axes that bear the leaves 

 fall with them in the autumn. 



The jioivers of the Coniferae are always unisexual, and the plants are either 

 monoecious, as in the Abietineae and Thuja, or dioecious, as in Taxus, the 

 Araucarieae and Juniperus communis; the male flowers are usually much more 

 numerous than the female. The flowers are never terminal on the primary stem, 

 and diff"er in this respect from those of the Cycadeae ; even the larger woody 

 branches seldom have terminal flowers, as in Abies excelsa where they are female ; the 

 flowers are usually either terminal on small leafy shoots of the last order, or spring 

 from the axils of the leaves of stronger shoots. In Thuja, for example, male and 

 female flowers appear on the end of small short leafy members of bilateral shoot- 

 systems, in Taxus and Juniperus in the axils of foliage-leaves of larger shoots ; in 

 Abies pectitiata both are formed on the under side of shoots of a higher order at the 

 summit of older trees and in the axils of foliage-leaves, the female singly, the male in 

 numbers ; the male flowers of Pinus sylvesiris and allied species are found in the 

 place of the small leafy shoots (spurs) in the axils of the scale-leaves of growing 

 woody shoots, usuall}- many in number and forming an inflorescence through which 



