perianth Bot.
(ˈpɛrɪænθ)
Formerly in L. form perianthium.
[app. directly after F. périanthe (Rousseau 1771–7), ad. mod.L. perianthium (17th c. in Ray), f. Gr. περί about + ἄνθος flower (after Gr. περικάρπιον: see pericarp).]
1. A structure surrounding, or forming the outer part of, a flower; a floral envelope. † a. In earlier use, a synonym of calyx; and, like it, applied also to an involucre or whorl of bracts, as that at the base of the flower-head in the Compositæ. Obs.
| α [1686 Ray Hist. Plant. I. 22 Semina..quæ nullo præter perianthium..tegmine donantur.] 1706 Phillips, Perianthium, or Calyx (among Herbalists) the Flower-cup in most Plants. 1748 Phil. Trans. XLV. 169 The Bud or Rudiment..appears in Autumn wrapped up in a conic scaly Perianthium. 1762 Ehret in Phil. Trans. LIII. 82 At the base of this..petal is situated an irregular..triphyllous periantheum. 1806 J. Galpine Brit. Bot. 44* Stratiotes. Spatha 2-leaved. Perianthium superior, 3-cleft. |
| β 1785 Martyn Rousseau's Bot. xxi, The early Hepatica..has a perianth of three leaves, which being remote from the flower, is rather an involucre than a calyx. Ibid. xxvi, The calyx or perianth common to the whole flower. |
b. Now, The outer part or envelope of a flower, which encloses the essential organs (stamens and pistils); either
double,
i.e. the calyx and corolla collectively,
esp. when so much alike as to appear to constitute a single part; or
single, when there is only one, which may be either green (
sepaloid) like an ordinary calyx, or coloured (
petaloid) like an ordinary corolla.
| 1828 Stark Elem. Nat. Hist. II. 477 The Dicotyledonous plants with a double perianth, but with the corolla formed of a single petal attached to the calyx. 1835 Lindley Introd. Bot. (1848) I. 326 The word Perianth signifies the calyx and corolla combined. 1857 Henfrey Bot. §189 A large number of the Monocotyledonous orders possess a petaloid perianth; that is, there are two circles of petaloid organs, which, from their resemblance, or their actual coherence, have the appearance of a single hexamerous whorl. 1880 Gray Struct. Bot. vi. §1 (ed. 6) 164. |
c. In liverworts, a leafy or membranous covering surrounding the archegonium; in mosses, the cluster of leaves surrounding the sexual organs in the ‘flower’.
| 1857 Henfrey Bot. §320 (Hepaticæ) The vaginule,..the circle of leaves, often confluent, surrounding it, form the perigone, perianth or involucel. 1866 Treas. Bot. 863 [In liverworts] the involucre and perianth coexist sometimes in the same plant. 1875 Bennett & Dyer tr. Sachs' Bot. 293 Besides the envelopes just named [perichætium, etc.], there is also often in Hepaticæ (but not in Mosses) a so-called Perianth, which grows as an annular wall at the base of the archegonium, and finally surrounds it as an open sac. |
2. attrib. and
Comb., as
perianth-leaf,
perianth-segment,
perianth-tube,
perianth-whorl.
| 1870 Hooker Stud. Flora 356 Herminium..Perianth-segments incurved. Ibid. 362 Trichonema..spathe longer than the perianth-tube. 1875 Bennett & Dyer Sachs' Bot. 556 Both of the trimerous perianth-whorls petaloid. |
Hence
† periˈantheous,
periˈanthial adjs., having, or pertaining to, a perianth.
| 1857 Mayne Expos. Lex., Periantheus, Bot., applied to a flower provided with a..perianth: periantheous. |