loo I 



PINUS 



Pinus, Linnaeus, Gen. PI. 293 {ex park) (1737); Duhamel, Traiti its Arbres, ii. 121 (1755); 

 Bentham et Hooker, Gen. PI. iii. 438 (1880); Engelmann, in Trans. Acad. St. Louis, iv. 161 

 (1886); Masters, in Journ. Linn. Soc. {Bot.), xxvii. 236, 248, 258, 269, 309 (1891), xxx. 37 

 (1893), and xxxv. 560 (1904); Mayr, Wald. Nordam. 425 (1890), and Fremdldnd. Wald- u. 

 Parkbaume, 340 (1906); Shaw, in Bot. Gaz. xliii. 205 (1907). 



Evergreen trees or shrubs, belonging to the division Abietineae of the order Coni- 

 ferae. Bark usually thick, rough, and deeply fissured ; but in some species thin and 

 scaly, and in a few others peeling off in thin flakes like a plane tree. Branches 

 arising from the stem in apparent whorls. Shoots of two kinds : short shoots, 

 which are minute spurs of limited growth, bearing the adult leaves in clusters and 

 deciduous with them ; and long shoots, the ordinary branchlets, which continue 

 growth. 



In the majority ' of pines, the long shoot produced in spring is a single internode, 

 consisting of (a) a leafless base, which bears the staminate flowers, when these are 

 developed ; and (b) a longer upper portion bearing foliage, and ending in (c) a terminal 

 bud, subtended by a whorl of smaller buds, one or more of which may be replaced 

 by pistillate flowers (young cones). The buds and young cones being close to 

 the apex of the shoot, are said to be subterminal. In the second year the mature 

 cones and the branchlets, which have developed from the single whorl of buds 

 of the first year, are situated beneath the base of the new shoot of the year, which 

 has sprung from the terminal bud of the preceding season. 



In another group ' of pines, the long shoot produced in spring consists of two 

 (rarely three or more) internodes, each with a leafless base, a leaf-bearing portion, 

 and a whorl of buds (with or without young cones). The buds and young cones 

 are in two or more whorls, and are both subterminal and lateral in position. 

 Similarly, in the second year, the branchlets and mature cones are in two or more 

 whorls. 



In young or vigorous trees of any species of either group the subterminal whorl 

 of buds and young cones, already formed in spring, is occasionally placed in a lateral 

 position by the development above it of a summer shoot, which is distinguished from 



1 Termed uninodal pines by Shaw. 



2 Multinodal pines of Shaw, who points out that when the trees are old or diminishing in vigour, they often produce 

 shoots with only one whorl of buds, but recognisable as having two internodes by the presence of two leafless bases ; or they 

 may, when very feeble, only develop one internode to each shoot. 



V IOOI B 



