. A manual of the Coniferae, containing a general review of the order; a synopsis of the hardy kinds cultivated in Great Britain; their place and use in horticulture, etc., etc. With numerous woodcuts and illustrations. Conifers; Evergreens. STRUCTURE OP CONIFEROUS cursory examination of the section shows the following arrangement of the parts: 1st—A central pith, which is larger or smaller according to the kind of tree or shrub to which the branch belongs, large in the Elder, smaller in the Sycamore, a mere point in the Oak; and also according to the age of the stern; it is always enve
. A manual of the Coniferae, containing a general review of the order; a synopsis of the hardy kinds cultivated in Great Britain; their place and use in horticulture, etc., etc. With numerous woodcuts and illustrations. Conifers; Evergreens. STRUCTURE OP CONIFEROUS cursory examination of the section shows the following arrangement of the parts: 1st—A central pith, which is larger or smaller according to the kind of tree or shrub to which the branch belongs, large in the Elder, smaller in the Sycamore, a mere point in the Oak; and also according to the age of the stern; it is always enveloped in a delicate network of vessels termed the medullary sheath. 2nd—Around the pith will be seen a series of rings or concentric circles, the number of such rings corresponding precisely with the age in years of the stem examined. 3rd—These rings are crossed by lines generally of a lighter colour, all radiating from the -central pith, and known Pig. 1. Transverse and by the name of medullary ravs. 4th—The whole longitudinal sections of a- , , , -,-,-,. ., three years old stem. is surrounded by, and enclosed m, a cuticle or covering familiarly called the bark. This form of structure is the result of the mode of growth of the tree or shrub. The pith is the remains of the cellular or soft tissue of the tender stem first produced from the seed in the primary shoot and its prolongation during its successive annual growths, or from a leaf bud in a lateral one. The concentric rings are the woody fibrous tissues with the spiral and other vessels which lie next the centre, and are the parts first formed by the growth of each succeeding year; the medullary rays are, as it were, the channels of communication during the circulation of the sap; first, between the central pith and the bark surrounding the first ring of woody fibre during its formation, next between the first ring and the bark during the formation of the second ring, and so on, the central portion becoming hardene
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectconifers, bookyear188
