perispermic 
embryo sac; (2) the pericarp or 
even the integuments of a seed; 
perisper’mic, perisper’micus, peri- 
sperma’tus, (1) furnished with al- 
bumen ; (2) ‘‘ when the perisperm 
is reduced to a single lamina, or 
when the seed is not furnished with 
a true perisperm” (Henslow) ; 
Perisporan’gium (copa, a seed, 
dyyeiov, a vessel), the indusium 
of Ferns, a membranous covering 
of the sorus; Per‘ispore, Peris- 
porium, -rum, (1) the membrane 
or case surrounding a spore; (2) 
the mother-cell of spores in Algae ; 
(83) = PEriIcyNiuM ; Peristach’yum } 
(ordxus, a spike), the glume of 
grasses ; Peristamin‘ia (+ STaMEN), 
Periste’mones (oTjuwv, a filament), 
applied to petalous dicotyledons 
with perigynous stamens; Per‘i- 
stem (fcrnu, I stand), young cortex 
in a nascent condition; Per’istome 
Perist'oma, Peristom'ium (ordua, 
a mouth), the fringe or its homo- 
logue round the orifice of a moss- 
capsule; perist/omate, peristoma’- 
tus, perist’omus, provided with a 
peristome ; peristomat’ic, peristo- 
mat'icus, when perigynous stamens 
are attached round the mouth of 
the calyx tube; peristy’licus ( + 
SryLus), when epigynous stamens 
are inserted between the styles 
and limb of the calyx; Perisy’phe 
more correctly PERISCYPHE ; Per‘i- 
thece = Perithe’cium, pl. Perithe’- 
cia (Oqxy, a case), (1), a case with 
a small opening containing asci, 
in Lichens; (2) in Fungi, a re- 
ceptacle enclosing spores which 
are naked or in asci; perithe’cioid 
(eldos, like) Glands, those oa the 
pitcher of Nepenthes, resembling 
the perithecium of a Sphaeria 
(Macfarlane) ; perit’ropal, perit’- 
ropous, -pus (tpory, a turning), 
used of a seed which is horizontal 
in the pericarp, or of a radicle 
which is directed to the side of a 
pericarp; perixylemat/ic (+ Xv- 
LEM), said of concentric bundles in 
the roots of Acorus, Juncaceae and 
190 
perpendicular 
Cyperaceae (Laux); perixy’lic, Van 
Tieghem’s expression for MESARCH 
+ EXARCH; Perizo’nium ({dvy, a 
belt), the thin non-silicious mem- 
brane of a young auxospore, 
perlar’ius, perla’tus (Late Lat., perla, 
a pearl), (1) shining with a pearly 
lustre ; (2) furnished with rounded 
tubercular appendages (Henslow). 
Norte: not to be confounded with 
perlatus, carried through, derived 
from perfero. 
per’manent, per’manens (permaneo, I 
persist), persistent ; ~ Tis’sue, fully 
formed tissue, as distinct from 
merismatic or generative tissue. 
Permeabil'ity (permeabilis, that can 
be passed through), applied to 
protoplasm, etc., and further dis- 
tinguished as EXTRAMEABILITY, 
and INTRAMEABILITY, the power 
of allowing the passage of certain 
substances out of or into its 
vacuoles respectively (Janse). 
Permuta'tion, Permuta’tio (Lat., a 
changing), enlargement of the 
floral envelopes with abortion of 
the sexual organs (Penzig). 
permuta’tus (Lat.), completely 
changed. 
Per’nio (Lat., a chilblain), a local 
affection resembling an_ ulcer, 
caused by cold. 
Perocid’ium { (epi, about, dyxidtov, w 
tubercle), Necker’s term for PERt- 
CHAETIUM. 
per’onate, perona’tus (Lat., leather 
booted), thickly covered with a 
woolly covering becoming mealy. 
Perovula'tae (per, much or very, 
ovulatus, ovuled), otherwise SEmr- 
NaTAE, Van Tieghem’s terms for 
phanerogams furnished with true 
seeds, 
perpe’lic (per, very, m7Ads, clay), 
Thurmann’s term for rocks which 
yield clay, pure and abundant, also 
the plants which thrive thereon; 
perpsam’mic (Wdpmuos, sand), yield- 
ing an abundance of sandy detritus, 
with the flora thereon growing. 
perpendic’ular, Bonnenicuid aa Ew ), 
used of an organ with its direction 
