Perigynium 
Perisperm 
woman, dvip, dvdpds, 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 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 (xdpvoy, a nut, 
mragua, moulded), a zone of 
granular protoplasm seen in Cobaea 
scandens, Cav., in the cytoplasm 
of the resting pollen mother-cell 
on its approaching division (A. 
A. Lawson); perimedul/lary (+ 
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 (-++MuERISTEM), 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 (zrep), about), the 
outermost layer of sculpturing on 
pollen ; perinectar’ial (+ Nzcrary), 
surrounding the nectarial area, 
as in certain Gentians (Huxley) ; 
Perin‘ium, the outermost of the 
three coats of 4 Fern spore; the 
epispore. 
perin’teger (Lat.), quite entire. 
Period’ic 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 (epi, about, 
métadov, a flower-leaf), around the 
petals. 
periph’eral (repipépera, the circum- 
ference of a circle), surround- 
189 
ing; ~ Tis’sue, in roots, the 
piliferous layer, furnished with 
root hairs; peripher’ic, peripher’i- 
cus, pertaining to the circumfer- 
ence, as of an embryo coiled round 
the outside of the albumen; 
peripher’ico-termina’lis, 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’ém (epi, about + PHLOEM), 
the phloém-sheath or pericambium ; 
periphloémat‘ic, applied to concen- 
tric bundles in Ferns ; Periphoran’- 
thium (dopéw, I carry, dvOos, a 
flower), the involucre of Com- 
positae ; Periphor’ium, a fleshy and 
elongated support to the ovary, 
with the corolla and stamens 
attached to it; Henslow spells 
it ‘‘Periforium”; Per’iphragm 
(ppdéyua, an enclosure), the peri- 
cycle of the stem (Dangeard) ; 
Per‘iphylls, Periphyl’lia + (pvAdov, a 
leaf), the hypogynous scales or 
lodicules of grasses; Periphyl- 
log’eny (yévos, race, offspring), 
bearing numerous leaflets round 
the edge of a leaf-blade (Weis- 
mann); Periph’ysis (¢’w, I grow), 
a sterile  capilliform hyphal 
branch, projecting from the wall 
of the pyrenocarp when there 
is no hymenium in the cavity 
(Fuisting); Per’iplasm (dopa, 
moulded), protoplasm in the 
oogonium and the antheridium 
which does not share in the con- 
jugation; ¢f. GonopLasm ; Per‘i- 
plast (7Adoros, moulded), a hyaline 
structure enveloping the cell- 
nucleus ; Peripod’ium (7ois, rods, 
a foot), = PrRICHAETIUM ; perip’- 
terous, -rus (wrepov, a wing), perip- 
tera’tus, surrounded by a wing or 
border ; Periscy’phe (cxv¢os, a cup), 
Desvaux’s word for PERICHAETIUM ; 
Per'isperm, Perisper’mium (orépua, 
a seed), (1) the ordinary albumen 
of a seed, restricted to that 
which is formed outside the 
