. Science-gossip . GOSSIP. 185 CHARACTERISTIC BRANCHING OF BRITISH FOREST-TREES. By the Rev. W. H. Purchas.{CoiiHntied from page 151.) The Oak {Queicus rohur, Linn.). IT has been thought by some botanists as wellas by foresters that we have in Britain twodistinct species of oak, the common or peduncledoak {Qucrcus pedunculata, of Ehrhart), and the sessile-fruited oak (0. sessiliflora, of Salisbury), to whichothers have been inclined to add, as a third species,or at least as a variety of Q. sessiliflora, the of Don. The botanical distinctions elude that the British oaks consti
. Science-gossip . GOSSIP. 185 CHARACTERISTIC BRANCHING OF BRITISH FOREST-TREES. By the Rev. W. H. Purchas.{CoiiHntied from page 151.) The Oak {Queicus rohur, Linn.). IT has been thought by some botanists as wellas by foresters that we have in Britain twodistinct species of oak, the common or peduncledoak {Qucrcus pedunculata, of Ehrhart), and the sessile-fruited oak (0. sessiliflora, of Salisbury), to whichothers have been inclined to add, as a third species,or at least as a variety of Q. sessiliflora, the of Don. The botanical distinctions elude that the British oaks constitute but a singlespecies. In the majority of cases, however, adifference in the mode of branching, which shallpresently be described, comes in to aid in the dis-crimination, and is often sufficient to enable us torecognise the sessile - fruited oak even in well remarks of this tree that, The growthof the spray or branching is freer and less tortuousthan in Q. pedunculata, that the leaf-buds are Qucrcus pedunculata. (Early summer state.) between these are found in the comparative lengthof the fruit-stalk or peduncle, which varies fromalmost nothing in some examples of Q. sessiliflora toa length of two, or even three, inches and more inQ. pedunculata, and also in the outline of the leaves,to which may be added a difference in the form ofthe winter buds and in the texture of their scales. In the case of the individuals which show thesedifferences at their maximum, it is not difficult todecide to which of the supposed species each indi-vidual should be referred ; but the inconstancy ofthe characters and the existence of intermediateforms have led most modern observers to con- and the bark in general much whiter in colour ; theleaves also, when expanded, are usually larger, andfrom the length of their petioles hang more looselyand present a less tufted appearance than they doin Q. pedunculata. (Selby, p. 248.) Arrangement of Leaves.—The leaves, and thebranche
Size: 1876px × 1332px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, booksubjectnaturalhistory, booksubjectscience
