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no more absolute than any other, for in P. montana (uncinata), 

 while the central shoot is leafy to the base, the lateral shoots 

 from the same cluster of buds are naked at the base. 



The shape of the young shoot soon after its emergence from 

 the bud is sometimes the same as at a later period, as in Picea, 

 where the shoots retain the cylindric shape they had at first ; 

 while at other times the shape of the shoot differs from that 

 which it assumes when the leaves are fully expanded ; for 

 instance, in Abies firma and A. homolepis the young shoot as it 

 emerges from the bud is spindle-shaped or cylindric, with the 

 leaves appressed to the axis on all sides, thus exposing to the 

 light their stomatiferous or lower surfaces. As growth goes on 

 the leaves, though really in many rows, arrange themselves in one 

 horizontal plane and become pseudo-distichous, some of them, 

 according to their place of origin, becoming twisted at the 

 base so as to allow of the exposure of the upper surface to the 



light, while other leaves differently placed require no such tor- 

 sion. 



Spurs. — The species of Larix, Cedrus, Pseudolarix, and 

 Ginkgo are remarkable for the production of two kinds or 

 branches, the one long and slender with the leaves distributed 

 at intervals, the other short, thick, with the leaves in tufts at 

 the extremities. The former are the extension or leader shoots 

 m which growth and development are rapid; the latter are 

 analogous to the similar growths in the Apple, Pear, Laburnum, 

 &c., but are (in the Conifers) not necessarily connected with the 

 development of fruit, although in Pseudolarix and Ginkgo, 

 however, the spurs bear the male flowers. In the Larches and 

 Cedars the " spurs " either remain as such or lengthen ultimately 

 into extension-shoots. The leaves on the extension-shoots are 

 generally longer and more g 7 aucous than those on the spurs, and 

 are stomatiferous on both surfaces. 



The mode of development of the spurs may readily be traced 

 in the Larch or Cedar, and confirms the view that the appear- 

 ances are due to the more vigorous growth of the basal and 

 peripheral parts in comparison with the central and apical 

 portions. Thus if the bud at the end of a shoot be examined in 

 October the apex will be found to be dome-shaped. The young 

 leaves emerge in succession from the base of the dome leaving 



^e apex naked, so that the development of the leaves is centri- 

 petal. 













































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