Perichaeth 
Perlgynandra 
ous stamensarranged concentrically 
with the calyx; Per’ichaeth 
(Crozier) = PERICHAETIUM ; Peri- 
chae’tium (xalry, a mane) ; (1) the 
involucre around the base of the 
seta in Mosses ; (2) Hooker’s name 
for the perianth in Hepaticae ; 
perichae’tial, perichactia‘lis, relat- 
ing to the same, as ~ Bracts, ~ 
Leaves, the organs composing the 
perichaetium itself in Moasae and 
the involucre in Hepaticae ; Per’i- 
chyle (xudés, juice), a plant 
whose water-storing tissue is 
between the epidermis and the 
chlorenchyma, as Rhizophora; 
Per‘icladium (x\ddos, a branch), 
the sheathing base of a leaf when 
it surrounds the supporting branch; 
pericli’nal (kA\ivw, E bend down), 
curved in the same direction as 
the surface or circumference; ~ 
Planes, planes which conform to 
the exterior ; Per’iclines, periclinal 
walls ; Pericli‘nium (xAivy, a bed), 
the involucre of the capitulum in 
Compositae ; Periclinoi’des,} a false 
involucre formed of the scales of 
the receptacle in Compositae, sur- 
rounding the sides of an elevated 
receptacle at its summit, as in 
Hvax; Pericoc’cium, that portion 
of the protoplasm which envelopes 
the nucleus; in Germ. Kerntasche 
(Hanstein) ; Pericol’ium + (kodeds, a 
sheath) = PrERICHAETIUM; peri- 
corolla’tus (+ CoROLLA), used of 
a dicotyledonous plant with a 
gamopetalous perigynous corolla ; 
Per‘icycle (xixdos, 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 ; Per‘iderm, 
Perider’ma, Perider’mis(s€épua, skin 
or hide), the outer bark or epi- 
phloém, at first restricted by 
Mohl to tough cork in distinction 
to the soft cork, now extended 
to the cork cambium and its pro- 
ducts ; phellogen ; Per’idesm (dé, 
a bundle), the layer of cells which 
188 
Perid’roma 
surround each vascular bundle 
beneath the special endoderm in 
astelic stems (Van Tieghem) ; adj. 
perides’mic. 
Perid‘iole, Perid'iolum, pl. Perid’iola 
(dim. of Peripiom from mnplé.ov, 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); Perid’inin, 
one of the colouring matters found 
in the Peridieae, a group of Fungi ; 
Perid’ium, a general expression for 
the outer enveloping coat of a 
sporophore upon which the spores 
evelop within a cavity; ~ ex- 
ter’‘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. 
(repdpou7, a circuit), 
Necker’s term for the rhachis of 
Ferns. 
Periench’yma (repl, about, éyxuua, 
an infusion), irregular cellular 
tissue, chiefly in glands and sphe- 
roidal masses (Henslow), cf. PER- 
ENCHYMA ; Perifor‘ium = PERI- 
PHORIUM ; Perigloe’a (y)oios, glue), 
the entire gelatinous investment of 
a Diatom (Buffham); Per’igone, 
Perigo'nium (yovh, offspring), (1) 
a synonym of PERIanTH ; (2) the 
same of PrERICcHAETIUM; (3) the 
involucre of the male inflorescence 
in Bryophytes; adj. perigo’nial, 
as ~ Leaves, the _perichaetial 
leaves (excluding Bryophytes) ; 
perigonia’rius, (1) with the char- 
acter of a perigone; (2) double 
flowers, resulting from transforma- 
tion or multiplication of the floral 
organs taking on the character of 
perianth segments ; Perigynan’da, 
Perigynan’dra, -drum (yu, a 
