Perigynium 



Perisperm 



woman, dvrjp, aj/5/jos, a man), (1) 

 the involucre of Compositae ; ~ 

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

 volucre, ~ inte'rior, the corolla of 

 a composite floret ; Perigynium, 



(1) the hypogynous setae of sedges ; 



(2) the flask or utricle of Carex ; 



(3) any hypogynous disk ; (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 pistil ; 

 Perikar'yoplasm (x&pvov, a nut, 

 TrXdo-jua, moulded), a zone of 

 granular protoplasm seen in Oobaea 

 scandens, Cav., in the cytoplasm 

 of the resting pollen mother-cell 

 on its approaching division (A. 

 A. Lawson) ; perimeduriary ( + 

 MEDULLARY) Zone, the peripheral 

 region of the inner tissue out- 

 wardly bounded by the pro- 

 toxylem ; cf. CIRCUMMEDULLARY ; 

 Perimel'itae (mel, honey), having 

 honey-glands placed in the lower 

 portion of the perianth, as in 

 certain Gentianaceae (Huxley) ; 

 Perimer'istem ( + MERISTEM), con- 

 sists of several layers of cells 

 which at first divide in every di- 

 rection, but subsequently divide 

 tangentially in the external region 

 (Guillaud); Per'ine (irepi, about), the 

 outermost layer of sculpturing on 

 pollen ; perinectar'ial ( + NECTARY), 

 surrounding the nectarial area, 

 as in certain Gentians (Huxley) ; 

 Perin'ium, the outermost of the 

 three coats of a Fern spore; the 

 epispore. 



perin'teger (Lat. ), quite entire. 



Periodic Move'ments, used to express 

 the opening and closing of flowers, 

 . the nyctitropic movements of 

 leaves, etc., when occurring habit- 

 ually and with some regularity. 



peripet'alous, -us (irepl, about, 

 ireraXov, a flower-leaf), around the 

 petals. 



peripheral (irepi<f)epeia, the circum- 

 ference of a circle), surround- 



ing ; Tis'sue, in roots, the 

 piliferous layer, furnished with 

 root hairs ; peripherlc, peripher'i- 

 cus, pertaining to the circumfer- 

 ence, as of an embryo coiled round 

 the outside of the albumen ; 

 peripherlco-terminalis, belonging 

 to the circumference and apex of a 

 body, used of stems which grow 

 both in length and breadth ; peri- 

 phae'ricus, peripheric, circumferen- 

 tial. 



Periphlo'em (irepl, about + PHLOEM), 

 the phloem-sheath or pericambium ; 

 periphloematlc, applied to concen- 

 tric bundles in Ferns ; Periphoran'- 

 thium (0o/>^w, I carry, avQos, a 

 flower), the involucre of Com- 

 positae ; Periphorlum, a fleshy and 

 elongated support to the ovary, 

 with the corolla and stamens 

 attached to it ; Henslow spells 

 it " Periforium " ; Perlphragm 

 ((fipdyfjut, an enclosure), the peri- 

 cycle of the stem (Dangeard) ; 

 Perlphylls, Periphyl'lia J (<t>v\\ov, a 

 leaf), the hypogynous scales or 

 lodicules of grasses ; Periphyl- 

 log'eny (yevos, race, offspring), 

 bearing numerous leaflets round 

 the edge of a leaf -blade (Weis- 

 mann); Periph'ysis (0tfw, I grow), 

 a sterile capilliform hyphal 

 branch, projecting from the wall 

 of the pyrenocarp when there 

 is no hymenium in the cavity 

 (Fuisting) ; Perlplasm (-rrXd^a, 

 moulded), protoplasm in the 

 oogonium and the antheridium 

 which does not share in the con- 

 jugation ; cf. GONOPLASM ; Perl- 

 plast (ir\d<TTos, moulded), a hyaline 

 structure enveloping the cell- 

 nucleus ; Peripod'ium (TTOVS, TroSos, 

 a foot), = PERJCHAETIUM ; perip'- 

 terous, -rus (irrepoit, a wing), perip- 

 tera'tits, surrounded by a wing or 

 border ; Periscy'phe (o-/cu'0os, a cup), 

 Desvaux's word for PERICHAETIUM ; 

 Perlsperm, Perisper'mium (<rT^a, 

 a seed), (1) the ordinary albumen 

 of a seed, restricted to that 

 which is formed outside the 



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