Pericolium 



perimedullary 



a sheath) = Perichaetium ; peri- 

 coroUa'tus {+ Corolla), used of 

 a dicotyledonous plant with a 

 garaopetalous perigynous corolla ; 

 Per'icycle {kvkKos, a circle), the 

 outermost zone of cells of the stele 

 immediately within the endodermis ; 

 inter'nal '^, Flot's term for the pro- 

 cambium retained on the inner side 

 of the vascular bundle ; pericy'clic 

 Sec'tors, interruptions of the peri- 

 cycle of the root in certain Mosses, 

 by tissues of cells whose walls are 

 very slightly thickened (Campbell) ; 

 Periderm, Perider'ina, Perider'mis 

 {dep/xa, skin or hide), the outer bark 

 or epiphloem, at first restricted by 

 Mohl to tough cork in distinction to 

 the soft cork, now extended to the 

 cork cambium and its products ; 

 phellogen; Per'idesm (SeV/iTj, a 

 bundle), the layer of cells which 

 surround each vascular bundle 

 beneath the special endodeim in 

 astelic stems (Van Tieghem) ; adj. 

 perides'mic. 



Perid'inin, one of the colouring-matters 

 found in the Peridineae. 



Perid'iole, Perid'iolum, pi. Perid'ioJa 

 (dim. of Peridium from ir-npiSiov, a 

 little pouch), (1) a chamber of the 

 gleba forming a nest of spores, free 

 or attached by a funicle within the' 

 peridium of the sporophore ; (2) 

 "a membrane by which the spores 

 of some Algae are immediately 

 covered" (Lindley); Peridium, a 

 general expression for the outer 

 enveloping coat of a sporophore 

 upon which the spores develop 

 within a cavity ; --' exter'num, 

 the outer layer which opens in 

 various ways and separates from 

 the ~' inter'num, the inner layer 

 directly enclosing the gleba ; '-- 

 mitrifor'me, " the receptacle of 

 certain Fungals " (Lindley); adj. 

 perid'ial ; as ~ Cells, the outer 

 cells of a peridium which are 

 coherent. 



Perid'roma (irepiSpofxi], a circuit), 

 Necker's term for the rliacliis of 

 Ferns. 



Periench'yina {irepl, about ; iyxvfxa, 

 an infusion), irregular cellular 

 tissue, chiefly in glands and sphe- 

 roidal masses (J. S. Henslow), cf. 

 Perenchyma ; Periforlum = Peri- 

 PHORiUM ; Perigamlum (7a/ios, 

 marriage), the portion of the fer- 

 tile reduced branchlets of Mosses, 

 which contain the archegonia ; 

 Perigloe'a {yXoios, glue), the entire 

 gelatinous investment of a Diatom 

 (Bull ham) ; Perlgone, Perigo'nium 

 [yovTfi, offspring), (1) a synonym of 

 Perianth ; (2) the same of Peri- 

 chaetium ; (3) the involucre of the 

 male inflorescence in Bryophytes ; 

 adj. perigo'nial, as '-- Leaves, 

 the perichaetial leaves (excluding 

 Bryophytes) ; perigonia'rius, (1) 

 with the character of a perigone; (2) 

 double flowers, resulting from trans- 

 formation or multiplication of the 

 floral organs taking on the character 

 of perianth segments; Perigynan'da, 

 Perigynan'dra, -drum {ywr), a 

 woman ; avi]p, avSphs, a man), (1) 

 the involucre of Compositae ; --' 

 commu'nis, '-' exte'rior, the in- 

 volucre, -^ inte'rior, the corolla of 

 a composite floret ; Perigyn'ium, 



(1) the hypogynous setae of sedges; 



(2) the flask or utricle of Carex ; 



(3) any hypogynous disc ; (4) the 

 involucre of the female inflor- 

 escence in Bryophytes ; perig'- 

 ynous, literally means round the 

 ovary, used of organs adnate 

 to the perianth, or adnate with 

 the lower part of the ])istil ; 

 perihadromat'ic ( + Hadrome), 

 surrounding the hadrome ; Peri- 

 kar'yoplasm {Kapvov, a nut ; ir\d(r/j.a, 

 moulded), a zone of granular proto- 

 plasm seen in Cobaea scaudens, 

 Cav., in the cytoplasm of the 

 resting pollen mother-cell on its' 

 approaching division (A. A. Law- 

 son) ; perileptomat'ic (-f Leptomr), 

 surrounding the leptome ; peri- 

 meduriary ( + medullary) Zone, 

 the peripheral region of tlje inner 

 tissue outwardly bounded by the 

 protoxylem ; cf. circummepullarv ; 



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