| 释义 |
periderm|ˈpɛrɪdɜːm|
[mod. f. Gr. περί around + δέρµα skin: in mod.F. périderme.]
1. Zool. A hard or tough covering investing the body in certain Hydrozoa.
1870Nicholson Man. Zool. 77 It is invested by a strong corneous or chitinous covering, often termed the ‘periderm’.
2. Bot. A name introduced (in Ger. peridermis) by von Mohl (1836), to designate the corky layers of plant-stems; subsequently extended to include the whole of the tissues formed from the cork-cambium of phellogen.
[1839Lindley Introd. Bot. (ed. 3) 89 The Epiphlœum of Link, Phlœum or Peridermis of Mohl, consisting of several layers of thin-sided tubular cells.] 1849J. H. Balfour Man. Bot. § 85 After a certain period,..the corky portion becomes dead, and is thrown off.., leaving a layer of tabular cells or periderm below. 1875Bennett & Dyer tr. Sachs' Bot. 81 The formation of cork is very frequently continuous, or is renewed with interruption; and when this occurs uniformly over the whole circumference, there arises a stratified cork-envelope, the Periderm, replacing the epidermis, which is in the meantime generally destroyed.
Hence periˈdermal a., of or pertaining to the periderm.
1884Bower & Scott De Bary's Phaner. 545 The peridermal structures always arise in a layer of cells which has already been differentiated. Ibid., The formation of bark is the immediate consequence of the internal formation of periderm, and the name is as a rule employed for the dried-up tissues and the adjacent peridermal layers conjointly. |