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UNITED STATES DEPARTMENT OF AGRICULTURE

Miscellaneous Publication No. 110

“GLOSSARY
OF BOTANICAL TERMS
COMMONLY USED
IN RANGE RESEARCH ”

Compiled by

W. A. DAYTON
Forester (Dendrology), Branch of Research
Forest Service

West nGT ON, D.C. oss sh ss) ss “ISSUED JULY. 1931
REVISED JUNE 1950

For sale by the Superintendent of Documents, Washington 25,D.C. - = © «+ e + Frice 20 cents

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UNITED STATES DEPARTMENT OF AGRICULTURE
MISCELLANEOUS PUBLICATION NO. 110

Issued July, 1931

Washington, DEC: Revised June, 1950

GLOSSARY OF BOTANICAL TERMS
COMMONLY USED IN RANGE RESEARCH

Compiled by W. A. Dayton, Forester (Dendrology),
Branch of Research, Forest Service’

FOREWORD

This glossary has been collated at the request of field officers of
the Forest Service primarily for use in connection with the impor-
tant western floras and other botanical publications which contain
no glossaries. ‘The text as originally prepared included only mor-
phological and taxonomic terms but has been enlarged somewhat
to include some of the more common terms used in plant ecology,
physiology, and other phases of botany, as well as a few of the more
common abbreviations and symbols used in the botanical sciences.

It is obvious that such a reference list as this can lay exceedingly
scant, if any, claim to originality but is essentially a compilation;
moreover, in view of the circumstances and the nature of these terms,
it seems neither necessary nor desirable to attempt to cite authorities
consulted; such authorities would be very numerous and, save per-
haps in a very few cases, could hardly be claimed as original sources
of terminology.

The argot of the botanical sciences is so voluminous that no effort
has been made to incorporate herein more than what appears to
be a fair share of the terminology in most common use.

SOME COMMON SYMBOLS USED IN BOTANICAL WORKS

0=absent, wanting, or none. co =an indefinite (mostly large) num-
© =(an) annual. er.
(@) = (a) biennial. !=indication that the writer has per-
2/ = perennial. sonally checked up and corrobo-
% =a hermaphrodite, or perfect, flower. rated a specific name, or other
° =pistillate, or female. citation of fact.
o' =staminate, or male. ?=indication of uncertainty, e. g.,
X =sign of a hybrid, or cross. that the writer is not sure that a
§ =a section, or subgenus. specific name used is the correct
5 =a shrub. one.
? an undershrub, or suffruticose °=feet; degree(s).
plant. ’=inch(es) ; minute(s).
>is greater than, is longer than, or | ”=line(s) (i. e., twelfths of an inch);
surpasses. second(s).
< =is less than, is shorter than. .. =therefore, hence.

+ =more or less.

1The writer wishes to express his appreciation to Frederick V. Coville and S. F. Blake,
of the Bureau of Plant Industry, for numerous valuable criticisms and suggestions. A
considerable number of the terms are illustrated by 76 small text figures, prepared under
the writer’s supervision: 70 by the late Mrs, A, EL Hoyle; 5 by Leta Hughey; and 1 by
C. L. Taylor. of the Forest Service.

Note.—Definitions not appearing in the 1931 edition are added on page 41.

2 MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

GLOSSARY

A-: A prefix (“alpha privative”) sig-
nifying ‘“ not,” as in apetalous, asep-
alous, asymmetrical, etc.

Abortive: Imperfectly formed or de
veloped ; rudimentary ; hence Sterile.

Acaulescent: Without a true or leafy
stem; having the leaves in a basal
tuft, the flowers or flower head
borne on a stalk (pedicel, peduncle,
or scape) from the ground. Thus
the common dandelion is acaules-
cent.

Acerose: Having a hard, sharp, needle-
like tip.

Achene (pronounced ay-keen’): A
small dry 1-seeded 1-celled inde
hiscent fruit; the fruit of sedges,
buttercups, composites, ete. (Fig. 1.)
Sometimes spelled akene.

A

FIGURE 1.—Achenes of
(A), a sedge (Oaren
sp.); (B), sunflower
(Helianthus annuus)

Acicular: Needle-shaped, as the leaves
(“needles”) of a pine tree.

Acorn: The characteristic, 1-celled,
1-seeded fruit of oaks (Quercus
spp.) ; it consists of a cuplike part
called the cup, cupule, or involucre,
and the glands or nut which con-
tains the embryo.

Aculeate: Beset with prickles (aculei),
as a rose or gooseberry bush.

Acuminate: Tapering gradually at the
end, or apex; taper-pointed; long-
acute. (Fig. 2, A.)

Cc

FIGURE 2.—Three types of ‘leaf
tips: A, acuminates3 B,
acute; C, obtuse. Other
types are illustrated in Fig-
ures 5 and 29

Acute: Terminating sharply and
abruptly in an angle of less than
SOs ACMI ees)

Adnate: Literally “ grown to” or “ad-
herent to”; said of parts that are

attached throughout their entire
length to other parts of a different
series; an adnate anther is so at-
tached to its filament.

Adventitious: Said of buds produced
without order or in an unusual place
on any part of a plant.

Adventive: A waif; a plant uninten-
tionally introduced from another

- locality but not-truly naturalized.
Used both as a noun and adjective.

Akene: Same as achene.

Alate: Winged ; provided with “ wings ”
(Latin, alae), or winglike append-
ages, as, for example, the fruits of

maples, angelicas, and fourwing
saltbush.
Alternate: Placed singly, not oppo-

sitely nor in pairs; first one and
then another, as leaves on a stem.

Alternation of generations: The alter-
nation of gametophyte and sporo-
phyte in the life history of a plant
species. Ferns furnish a familiar
example of this phenomenon (which
is sometimes called heterogenesis) ;
the gametophyte (plant which bears
the sex organs) is a minute, flattish,
green plant (called the prothallus
or prothallium), whereas the asex-
ual generation, the
sporophyte, is the
large plant ordi-
narily recognized
as a fern. This
phenomenon is one
of great scientific
and evolutionary
interest and, in
modified form, oc-
curs in the higher
plants as well. It
occurs also in the
animal world,
the hydroid jelly-
fishes and medusas
being well - known
examples.

Ament: A _ bracted,
pendulous’ spike;
acatkin; asin
birches, alders,
poplars, oaks, ete.
(Fig. 3.)

* FIGURD 38.—AnD
Amphitrop ous: ament, or cat-

Half anatropous; kin, as in
said of ovules hav- birch (Betula)
ing a short raphe,
the hilum, or place of attachment,
about in the middle of one side of
the ovule.

Anabolic: Of or pertaining to anabol-
ism.

Anabolism: That phase of metabolism,
or the life processes of plants, which

GLOSSARY OF BOTANICAL TERMS 3

relates to the building up or con-
structive processes.

Anatropous: Upturned or inverted;
said especially of ovules. An ana-
tropous ovule has its micropyle (ori-
fice through which the pollen tube
fertilizes the embryo) bent down
and adjoining the funicle, or funic-
ulus (ovule stem), to which it
more or less adheres as a raphe.

Androgynous: A term applied to those
sedges (Carex spp.) which have
male and female flowers in the same
spike but the male flowers upper-
most, so that only the lower part of
the spike bears fruit. The converse
of gynaecandrous.

Angiosperm: A member of the Angio-
spermae, or angiosperms, the larger
of the two groups (of which the
other is the Gymnospermae) into
which flowering, or seed-producing,
plants are divided. Angiosperms
have their seeds inclosed in an
ovary.

Annual: Enduring for not more than
a year. A plant which completes its
entire life cycle from germinating
seedling to seed production and
death within a year. It is, of
course, somewhat difficult to draw a
sharp line, especially in warmer and
drier countries, between annuals and
biennials. In colder climates typi-
cal annuals do not survive the win-
ter, but the so-called winter annuals
germinate in late fall or spring, are
dormant through the winter, and
complete their life history the follow-
ing spring. Annual is often ex-
pressed by the symbol © or @.

Annular: Ringlike; in the form of a
ring (Latin, annulus).

Anther: The essential
or pollen-bearing part
of the stamen; a
(usually 2-celled) pol-
len sac. Fig. 4.)

Antheridium: (pl. -ia):
The male organ of re-
production in ferns
and mosses, Corre- Ficurn 4—
sponding to the an- a, anther ;
ther of a flowering ae os
plant. filament

Anthesis: F'10 wering;
the time or action when the floral
envelope opens, the pollen is ripe,
and the stigma is in condition to
receive it.

Apiculate: Ending in a short, sharp,
abrupt, rather soft tip; said often of
leaves, leaflets, and sepals which
have the midrib prolonged a little

into a short, somewhat awnlike but
not rigid tip. (Fig. 5, A.)

A B C

Ficurp 5.—Three
types of terminal
pointing, as in
leaves, leaflets, pet-
als, and sepals: A,
Apiculate; B, cus-
pidate; C, mucro-
nate

Appressed: Lying flat or closely against
another organ or part; not spread-
ing; said, for example, of leaves
against the stem, and of branches of
the inflorescence to its main axis.

Approximate: Situated close together,
but not united; ‘“‘ next to” or “near
to.”

Aquatic: Of or pertaining to water;
growing in water. A plant (or ani-
mal) inhabiting water.

Arachnoid: Beset
with cobwebby
hairs (Greek,
arachnion, a
spider’s web);
as, for example,
the arachnoid
lemma of Ken-
tueky blue
grass. (Fig. 6.)

Arboreous: Tree-
like, having the
form, size, dura-

FIGURE 6.—Lemma
of Kentucky blue-

tion, or struc- grass (Poa pra-
ture ofa treeas tensis) showing

webby) hairs at
from an herb or base ue

shrub. Also

(1) of, pertaining to, frequenting, or
growing on trees; (2) wooded, or
abounding in trees.

Arborescent: Treelike in size or form,
or both. Literally, ‘“‘becoming a
tree”; strictly, arborescent repre-
sents a stage below that of arbore-
ous, but it is now commonly used,
instead of that term, for plants hav-
ing the tree habit and size.

Archegonium (pl. -ia) : The female re-
productive organ in ferns, mosses,
and their allies, analogous to the
pistil in a flowering plant.

Arcuate: Bow-shaped, or bowlike.

Areola (pl. -ae) : A small open space;
specifically: (1) In leaves, a space

4 MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

between the veins, or (2) in cacti,
the restricted circular areas where
the spines and spicules are borne.

Aril: A fleshy growth from the apex
of a seed stalk or the placenta,
which envelops or becomes attached
to the seed. Famiiiar examples are
seen in species of waterlilies and in
bittersweet and its congeners
(Euonymus spp).

Aristate: Provided with an
(Latin, arista) ; awned.

Articulate(d): Jointed, having a node
or joint (Latin, articulus).

Ascending: Upcurved; growing or di-
rected obliquely upward.

Asexual: Without sexual conjugation;
a term used in reproduction; thus
a grass which propagates by root-
stocks is said to exhibit asexual re-
production.

Aspect: The gross physical appear-
ance of a plant or other organism.

Assimilation: The complex process of
forming protoplasm in the plant.
Anabolism and metabolism convey
similar meanings, but anabolism re-
fers only to building-up processes in
the plant, whereas metabolism also
includes the catabolic, or disinte-
grating processes.

Association: A unit of vegetation; a
group of associated plants. There
is no one definition of the term as-
sociation that is entirely satisfac-
tory to all plant ecologists, but there
is fairly general unanimity of opin-

ion that the
term associa-
tion should be
confined to the
larger or more
fundamental
plant growth
groupings, 45S,
for example,
“the yellow pine
association of
the far West”.
Assurgent: As-
cending, espe-
cially when ris-
ing by curving
obliquely up-

awn

HIGUEE a wards.

ate leaf, as in fe

mountain mag- Attenuate: Long
nolia (M. fra or Slender ta-
seri); the ear- pering; becom-

like lobes at the
base of the leaf
blade are the au-
ricles

ing slender or
very narrow.

Auricled: Having
auricles, or
small earlike appendages or lobes,
usually at the base. (Fig. 7.)

Auriculate: Same as auricled.

Awn: A bristlelike appendage, espe-
cially on the floral bracts of grasses

or on the achenes of composites; the
“beards” of wheat, rye, ete.,.are
awns. (Fig. 8, a.)
Awned: Provided with awns; bearded.
Axil: The upper angle formed between
a plant stem or other axis and any
leaf, branch, or organ arising from
it; the axil of a
leaf is the point
or angleon theup-
per Side at the
base of the leaf-
stalk or of a Ses-
sile blade.
Axile: Belonging to
an axis, aS an
axile (central)
placenta.
Axillary: Oforper-
taining toanaxil;
occurring in or
borne at an axil.
Baceate: Berry-
like,
Banner: Topmost
petal in the corol-
la of a member of
the pea family

(papilionaceous
flower) ; Same aS wicuRE 8.—Floret
standard and it a nee ares
; : ipa sp.)3; a,
coe (Fig. Aw: t. Bede oF
» & ; fruit (caryopsis
Barb: A twin, permanently in-
sharp, down-_ vested by the in-

wardly or hack. | 5. Cae

wardly project-
ing point termi-
nating a bristle
(fig. 10,A),ason
the fruits of krameria and of certain
borages and umbellifers.

Barbate: Bearded.

Barbed: Beset with barbs,

callus. The
callus and base
of the awn are
plumose, i. 4,
feathery

FicuRB 9.—Flower of
peavine (Lathyrus
Banner
also as
standard and vexil-
lum)

Barbellate: Minutely bearded with
short stiff hairs; also Sometimes
used as a synonym of “ barbed.”

Basifixed: Attached by the base.

Bast: The strong woody fibers in the
bark of trees and other woody

GLOSSARY OF BOTANICAL TERMS 5

plants from which cordage is often
manufactured; see ‘ cambium.,”

Beak: A narrow, usually rather elon-
gated, necklike appendage, as on
the fruit of common dandelion.
(Fig. 11.)

Berry: A usually small simple fruit

having a fleshy pericarp. Grapes,
huckleberries, and currants are fa-
miliar examples.

B

FicgurRB 10.—A,
Compoundly bar-
bellate, barbed, or

glochidiate (in
this case double
_barbed) tip of
bristle on fruit of
American carrot

(Daucus pusil-
lus); B unci-
nate, or hooked

tip of bristle on
fruit of Caucalis
microcarpa, a
common annual
southwestern
umbellifer

Bi-: A prefix (Latin) signifying
“ twice,” “ two,” or ‘ double.”

Biennial: Enduring for two years. A
biennial is an herb which germinates
(typically in the spring of) one
year and flowers, fruits, and dies
(typically in the fall or winter of)

A B C

FIGURE 11.—Beaks. A, Keel apex of
flower of pointvetch (O#ytropis sp.) ;
B, apex of fruit of aniseroot, or
sweet cicely (Osmorhiza divaricata) ;
C, fruit of certain species of agoseris
(Agoseris spp.) ; a, pappus; 0b, beak
or necklike constriction of achene;
c, achene body

the succeeding year. Winter annu-
als, which germinate in the fall of
One year and die the following
spring, are not true biennials, since

they complete their life history
within one year of elapsed time. Bi-
ennial is often expressed by the
symbol @).

Bilabiate: Two-lipped ; as, for example,
the flowers of many members of the
mint family (Menthacese) and fig-
wort family (Scrophulariacez).

Bipinnate: Twice pinnate, as of a pin-
nate leaf that is again divided into
leaflike parts. (Fig. 12.)

FIGURE 12.—Bipinnate leaf of
false-mesquite (Calliandra).
Each main leaf division is a
Pinna, while the small indi-
vidual leaflets are pinnules

Bipinnatifid: Twice pinnatifid ; that is,
having the primary division, as of a
pinnate leaflet, again cleft into seg-
ments or lobes. (Fig. 138.)

FIGURE 13.—Bipinnat-
ifidleaf. Each main
division (pinna) is
pinnately lobed, cleft,
or sometimes even
parted, but not di-
vided

Blade: The lamina, or broad portion
of a leaf, petal, etc. A leaf consists

‘ either entirely of a blade (lamina)
or else of a blade and petiole
(stalk).

Bract: A leaflike or scalelike organ
subtending a flower or aggregation

6 MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

of flowers; a modified inflorescence
leaf.

Bracted: Provided with bracts or com-
posed of bracts; as the bracted in-
volucre of the aster (composite)
family.

Broad-leaved herb: A ‘“ weed” in the
range Stockman’s sense; a nongrass-
like herb.

Browse: Twigs and shoots, with their
leaves, cropped by livestock from
shrubs, trees, and woody vines. One
of the four commonly recognized
classes of range forage, the others
being grasses, grasslike plants, and
weeds.

Bryophyte: A moss or moss ally; a
member of the natural plant group
of Bryophyta.

Bulb: A (usually subterranean) leaf
bud, composed of fleshy scales. Not
a root, although often supposed,
popularly, to be such.

Caducous: Falling very early; very
early deciduous; as the caducous
sepals of poppies. Partly synony-
mous With fugacious.

Caespitose: Tufted; having the stems
in a tuft, as a bunch grass.

Callus: A hard point; specifically the
hard, sharp-pointed base of certain
grass seeds, as in the genus Stipa.
(Rize S63)

Calyx (pl. -yces): The outer series of
the floral envelope, or perianth; the
parts immediately below the corolla;
the sepals as a unit. (Fig. 14, @.)

FicurE 14.—Flower of

wallflower (Cheirinia
sp.); a, Stigma and
pistil; 6, the four pet-
als which constitute
the corolla; c, the six
stamens; d, three of
the four sepals which
constitute the calyx;
e, the pedicel; b and
d@ together constitute
the perianth

Cambium: The thin, mucilaginous, cel-
lular layer between the wood of a
tree and its inner bark. This layer
is the living portion which is an-
nually converted into wood on its
inner surface and bark on its outer,

thus bringing about the thickening
of the tree trunk.
Campanulate: Bell shaped.
Campylotropous: Literally, bent
(curved)—turned; said of curved
ovules or seeds one side of which has
grown faster than the other so that
the micropyle (orifice) is near the
hilum (point of attachment), the
embryo also being curved. An out-
standing character of chickweeds,
portulacas, and certain other plants.
Cancellate: Chambered, or cell-like.
Canescent: Hoary, with fine grayish
pubescence; grayish white.
Capillary: Hairlike.
Capitate: Headlike or head shaped;
borne in a head or dense cluster.
Capitulum: Same as head, especially
if small.

Capsule: A pod; a dry dehiscent fruit
or seed vessel composed of two or
more carpels. (Fig. 15.)

FIGURE 15.—Capsules of: A, Pentstemon
sp.; B, false-hellebore (Veratrum cali-
fornicum) ; C, Iris sp.

Carinate: Keellike;
keel of a ship.

Carpel: A simple pistil;: the modified
leaf of which the ovary is formed;
also, a part of a compound ovary.

Carpophore: A carpel-bearing part;
the central organ from which a Car-
pel depends, as
in anumbellifer.
(Fig. 16, 0.)

Caryopsis: The
fruit of a grass;
a grain. The
seed and fruit
are united, the
seed adhering
to the thin
pericarp, _ or
outer covering
of the” few
throughout.
(Fig. 8, 0.)

Catabolic: Of or pertaining to catab-
olism.

Catabolism: The chemical and physi-
cal processes involved in cell decay

keeled like the

FIGURE 16.—Fruit of
an umbellifer: a,
Twin mericarps;
b, carpophore

GLOSSARY OF BOTANICAL TERMS 7

or the use of energy (as opposed to
anabolism) ; the destructive or dis-
integrating life forces. Catabolism
is the negative phase of metabolism.
Frequently spelled katabolism.

Catkin: A bracted, pendulous spike;
an ament. (Fig. 3.)

Caudate: Provided with a tail (Latin,
cauda).

Caudex: The trunk or woody axis of
a tree; the woody base of a peren-
nial plant.

Caulescent: Producing a stem above
ground. The opposite of acau-
lescent.

Cauline: Of or pertaining to the stem;
cauline leaves are leaves which are
borne on the main plant stem or its
branches.

Cell: A chamberlike part or organ;
the structural unit of an organism,
whether plant or animal. A cell is
usually microscopic and largely con-
sists of protoplasm surrounded by a
cell wall; its most essential part is
the nucleus which is fundamental
in the growth, metabolism, and re-
production of both plants and ani-
mals.

Centrifugal: Proceeding from the cen-
ter to the outer edge; the order of
flowering in a cyme (or other de-
terminate inflorescence) is cen-
trifugal.

Centripetal: Proceeding from the outer
edge or periphery inwards to the
center. In an indeterminate in-
florescence (aS a corymb, panicle,
raceme, spike, and umbel) the order
of flowering is centripetal, the out-
ermost or lowest flowers opening
first and setting seed first, and the
innermost or uppermost flowers and
fruit maturing last.

Cernuous: Nodding.

Cf.: Compare (Latin, confere). Used
especially to indicate that authentic
material of the plant in question is
not at present available.

Chalaza: That part where the integu-
ments, or coats, of the ovule cohere
with each other and with the nuw-
cleus (Greek, pimple or sty).

Chartaceous: Papery or paperlike in
texture.

Chlorophyll: The complex nitrogenous
substance, occurring only in chloro-
plasts, responsible for the prevalent
green hue of the vegetable kingdom.
In alge and certain other plants
the green hue is frequently obscured
by other pigments. Chlorophyll is
essential to the formation of starch
and other carbohydrates in plants
and, if absent altogether, the plant
is a parasite or Saprophyte, depend-

ing on chlorophyll-bearing hosts for
its existence. Sometimes _ spelled
chlorophyl.

Chloroplast: A minute flattened body
occurring in a cell and containing
the chlorophyll. Chloroplasts are
found only in cells exposed to light
and containing iron.

Choripetalous: Having each of the
petals separate and distinct. For
example, the corolla of a geranium
is choripetalous. Polypetalous is a
synonym but has been largely re-
placed, chiefly because it implies
that the petals alSo are numerous.

Chorisepalous: Having the sepals dis-
tinct rather than united (gamosep-
alous); largely synonymous with
polysepalous. Thus, geraniums
have the calyx composed of five dis-
tinct sepals (chorisepalous, or poly-
sepalous), but mints have a united,
somewhat bell-like, gamosepalous
calyx, the five sepals being indicated
by five terminal teeth.

Ciliate: Hair fringed; provided with
eyelashlike hairs on the edge, or
margin. (Latin, cilium, eyelid.)

Cinereous: Ashen; said especially of
an ashen-gray pubescence.

Circinate: Coiled spirally in one piane,
like a watch spring or bishop’s
crozier, aS in an
unfolding fern
frond; partly
synonymous
with scorpioid.
(Fig. 17.)

Circumscissile:
Dehiscing or
opening trans-
versely, the top
separating like
a lid, as, for ex-
ample, the cap-
sule or pod
(pyxis) of por-
tulacas.

Clavate: Club
shaped.

Cleft: Cut about halfway to the mid-
vein or base, especially when the in-
cision is sharp; Said, for example,
of leaves. (Fig. 18.)

Cm.: Centimeter(s),
two-fifths of an inch.

Collenchyma: A tissue of elastic, non-
woody, frequently elongated
strengthening cells; plant’ tissue
composed of cells thickened at the
angles. It contains a large amount
of protoplasm and is very charac-
teristic of actively growing (espe-
cial young and tender) vegetative
parts.

FicurRE 17.— Circi-
nate frond of a
fern unfolding in
early spring

approximately

8 MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

Composite: A member of the aster, or
composite, family (Asteracex, or
Composite).

Coma: Hair, especially if tufted, dense,
long, and soft. (Latin, coma).

Comb. nov.: New combination (Latin,
combinatio nova), i. e., a hitherto
unpublished scientific plant or ani-
mal name based on a rearrangement
of names already published.

&

)

AS
n

FIGURE 18.—Cleft, as the
leaves of certain oaks
(Quercus spp.)

Compound: Composed of two or more
separate but similar parts joined to-
gether. A compound leaf, for ex-
ample, is composed of Separate leaf-
lets. (Figs. 12, 13, 28, and 46.) A
compound ovary is composed of two
or more carpels.

Cone: The (often conical) dry multi-
ple fruit of pines, spruces, firs, hem-
locks, and other conifers, consisting
of numerous partially overlapping
(imbricated) scales arranged sym-
metrically around a central axis and
bearing naked seeds on their upper
surface. Same as strobile.

Conelet: A small or immature cone.

Confluent: Running together; blended
in one.

Congener: A plant of the same genus.
Thus, white pine and yellow pine
are congeners.

Congeneric: Belonging to the same
genus. Thus nightshade, eggplant,
potato, Jerusalem-cherry, and horse
nettle are congeneric, Since all are
species of the genus Solanum,

Conifer: Literally, cone bearer. A
member of the pine family
(Pinacez, or Conifer). .

Connate: More or less completely
united (said of similar organs), as
the connate leaves (fig. 19) and ber-
ries of honeysuckles (Lonicera
spp.).

Consocies: An associated group of
plant societies; the main subdivision
of a plant formation.

Contorted: Twisted together; twisted.

Ficgurp 19.—Connate, as the
leaves of certain honey-
suckles (Lonicera spp.)

Convolute: Literally, rolled together,
rolled up lengthwise, either with one
edge rolled inside as a sheet of paper
is ordinarily rolled, or both edges
rolled toward each other, forming a
sort of tube, as in many grass
leaves. In the latter case the blades
may be either involute or revolute.

Cordate: Heart shaped; i. e., notched
and with two rounded lobes at the
base. (Fig. 20.)

FIGURE 20.—Cordate
leaf of common

catalpa (Catalpa
bignonioides)

Coriaceous: Of a thick, leathery tex-
ture (Latin, corium, hide or skin).

Corm: A swollen or enlarged, rounded,
solid, fleshy, mostly subterranean
stem base. Like a bulb in shape and
appearance, except that it is solid,
instead of being composed of fleshy
seales.

Corolla: The inner series of the floral
envelope (perianth) parts; the pet-
als as a unit. The five petals of a
geranium blossom compose its ¢Co-
rolla. A corolla may be composed
of separate petals (choripetalous,
or polypetalous) (fig. 14, b), or
have the parts united (gamopetal-
ous, or Sympetalous).

GLOSSARY OF BOTANICAL TERMS 9

Corona: A crown, or crownlike organ
or part, as in the flower of a milk-
weed (Asclepias). (Fig. 21.)

Corymb: A con-
vex or flat-
topped open
flower cluster,
with the pedi-
celS arising
from different
points on the
stem, the flow-
ers developing
from axillary
buds and the
outer and lower

. Figure 21.—Flower
ones blooming of a milkweed (As-

earliest _— (fig. clepias Sp.) 3: 4a,
22), the inflo- TueHEyCo UCr ae of
r corona hoods; 8b,
eee a: ge corona, composed
eing indeter- of five hoods, or
minate and cen- cucullate, petaloid
tripetal. SeSmeDES C, ce
A rona column; d,
Corymbose: five reflexed co-
Borne in a co- rolla segments, or
rymb; corymb- petals; e, pedicel

like. (Fig. 22.)

Cospecific: Belonging to the same
species.

Costate: Ribbed.

Cotyledon: An embryo leaf or seed
leaf; the leaf, or one of a pair or

FIGURE 22.—Corymbose inflores-
cence, as in yarrow (Achillea)

whorl of the first leaves put forth
from a sprouting seed. The number
of cotyledons is of primary impor-
tance in the classification of flower-
ing (seed) plants. Thus, a grass or
sedge is always a monocotyledon;
legumes are always dicotyledons.
Cotype: Specifically, one or two or
more specimens on which the origi-
nal description of a species, variety,
or other nomenclatural unit is based,
when such species, variety, or other

892075 O- 50-2

Crenate: Scal-

Crucifer: A mem-

nomenclatural unit evidently rests
on more than one specimen and the
author neglects to indicate a type;
a specimen of the original series on
which a nonholotypic species (or
other nomenclatural unit) is based;
a part type (Syntype is also occa-
Sionally used to convey the same
idea). Also, but loosely, an isotype.
paratype, or duplicate of a _ type
specimen, i. e., a plant (or animal)
of the same species (or other nomen-
clatural status) as the type specimen
(holotype) and collected simultane-
ously at the same site by the same
collector.

Cremocarp: The peculiar dry twin

fruit, characteristic of the parsnip,
or umbellifer family (Apiacez,
Pastinacaceex, or Umbellifere) , which
separates at maturity into a pair of
opposite, indehis-
cent, 1-seeded
earpels (meri-
carps) pendu-
lous by thread-
like appendages
from a central
axis (placenta, or
carpophore). A
form of schizo-
carp. (Fig. 23.)

loped; having

FIGURE 23.—Crem-

teeth on the mar- parent: or other
: 5 umbellifer; @ a,

S 7 pendulous on

nutely crenate. threadlike ap-

pendages from
the carpo-

ber of the mus- phore; oc, pedi-
tard or crucifer Ga ee af Bas
family (Brassi- on each meri-
cacese, or Cruci- ‘carp is the per-
fere). Literally, sistent base of

the style (sty-

“cross bearer,” lopodium)

alluding to the
4-petaled, cross-shaped flowers.

Cryptogam: A nonseed-producing plant

of lower rank than the flowering
plants. Thus, fungi, alge, lichens,
mosses, and ferns are cryptogams.

Cucullate: Hooded (Latin, cuculla, a

hood). (Figs. 24 and 82, A, g, and
B, g.)

FicgurE 24.—Cucul-
late petal of flower
of Ceanothus

Cucurbit: A plant of the squash, pump-

kin, or melon family (Cucurbita-
ces).

10

Culm: The jointed stalk or stem, usu-
ally hollow save at the nodes, and
mostly herbaceous, of a plant be-
longing to the grass family (Poa-
ces, or Gramines). The term is
also frequently applied to the usu-
ally solid stalks of grasslike plants
(sedges and rushes).

Cuneate: Wedge shaped.

Cupule: A small cup; specifically, the
involucre, or cup, of an acorn.

Cuspidate: Tipped with a sharp and
rigid point, or cusp, especially if
lance or spear shaped. (Fig. 235,
A.)

A B C

FIGURE 25.—Three types
of terminal pointing,
as in leaves, leaflets,
petals, and sepals:
A, Cuspidate; B, Mu-
cronate; C, apiculate

Cylindric(al): Shaped like a cylinder;
elongated, and round in cross sec-
tion. Similar to terete.

Cyme: A flower cluster (often flat
topped or convex) in which the cen-
tral flowers bloom earliest. (Fig.
26.) The inflorescence represented
by a cyme is determinate, since the
original flowers always come from
terminal buds (and the main axis,
therefore, of the inflorescence can
not continue to develop), although

inflores-
Catchfly

FIGURB 26.—Cymose
cence, as in the
genus (Silene)

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

Cymose: Arranged in cymes; cyme-
like. (Fig. 26.)

Cytology: The science of plant and
animal cells, their structure and
functions.

D. b. h.: Diameter breast high (said
of trees).

Deciduous: Falling away; not persist-
ent or evergreen. Said, for exam-
ple, of leaves which drop off in
autumn or of a calyx and petals
which fall before the fruit is
formed.

Decompound: More than once com-
pound.

Decumbent: Reclining on the ground
but with the end ascending ;* bending
horizontally at the base. Said of
stems. Decumbent conveys the idea
of weakness.

Decurrent: Extending down or pro-
longed upon another part; said es-
pecially of leaves whose petioles or
blade bases are perceptibly pro-
longed along the plant stem, pro-
ducing a winged appearance of the
latter.

Decussate: Arranged in pairs at right
angles to the next pair immediately
above or below, suggesting when
looked down upon the form of a
Maltese cross. A number of milk-

weeds (Asclepias spp.) afford fa-
miliar illustrations of decussate
leaves.

Deflexed: Bent or directed abruptly
downward.

Dehiscent: Opening by valves, slits,
etc., to discharge the contents.
Anther cells dehisce to emit pollen.

Deliquescent: Literally, dissolving.
Said of tree trunks which do not
have a well-defined central axis.

Ficurn 27.— Deltoid
leaf form, as in cer-
tain species of as-
pen (Populus)

Thus oaks (Quercus) usually have a
deliquescent habit.

flowers may subsequently arise from | Deltoid: Deltalike; broadly triangular

axillary buds lower down on the
stem,

and shaped like the Greek letter
Any (hiss 2)

GLOSSARY OF BOTANICAL TERMS 11

Dendrology: That port of botany
which deals with trees. Ordinarily
the term is confined to taxonomic
and morphological investigations of
trees, other phases of tree science
being dealt with by forestry, arbori-
culture, horticulture, ecology, phyto-
pathology, ete.

Density: The relative degree to which
vegetation covers the ground sur-
face, and often expressed in tenths,
1.0 indicating a complete ground
cover of such vegetation. Specifi-
cally in range reconnaissance in the
Forest Service, ‘average density ”’
is a term used to indicate the pro-
portion of ground surface actually
covered by herbaceous or shrubby
vegetation within reach of livestock,
the lateral spread of the plant foli-
age, stems, and branches above
ground being carefully considered.
The density of grasses is based on
the spread when the plants are
grazed to the proper extent rather
than on the normal plant spread
when wungrazed or the reduced
spread when total use has been
made of the plant. The density of
erect weeds is based on the amount
of ground that appears covered
when the vegetation is viewed from
directly above. The density of
browse is estimated from the ground
surface covered by that part of the
browse that is readily accessible to
livestock.

Dentate: Toothed, with the “teeth”
nearly equal sided, projecting for-
ward or at a right angle rather than
upward, and usually being acutish.
(Fig. 30, C.)

Denticulate: Minutely dentate.

Depauperate: Dwarfed, starved. Said
of small, impoverished, undeveloped
plants grown in poor soil or under
otherwise unfavorable conditions.

Depressed: Vertically flattened; i. e.,
as if pressed downward from above.

Determinate: Having a centrifugal in-
florescence, the order of flowering
being from the center outward or
from above downwards, the main
axis terminating in a flower. Lit-
erally terminated or ended, the main
axis of the inflorescence being
estopped from further growth. The
cyme is probably the most familiar
example of determinate inflores-
cence.

Dextrorse: Spirally twisting to the
right. Said of vines that twine
counterclockwise, as dodder and
hops.

Di-: A prefix (Greek) signifying two,
or double.

Diadelphous: Having the stamens more
or less united by their filaments into
two groups, or clusters; literally,
two brotherhoods. The stamens of
most clovers and of many other leg-
umes are diadelphous.

Dichotomous: Two-forked, the forks,
or branches, regular and nearly
equal.

Dicotyledon: A plant whose embryo
and germinating seedling has two
cotyledons, or seed leaves. The
dicotyledons form one of the two
main groups into which angiosperms
are separated, the other being mono-
cotyledons.

Didynamous: Having four stamens ar-
ranged in two pairs, one pair
noticeably longer than the other.
For example, the stamens of many
members of the figwort family
(Scrophulariaceez) are didynamous.

Diffuse: Loosely, widely, and irregu-
larly spreading, the branches usu-
ally numerous.

Digitate: Fingerlike; compound with
similar parts radiating from a com-
mon point; as the digitate leaflets
of lupine. (Fig. 28.) The same as
palmate.

Ficurbn 28.—Digitate leaf of lu-
pine (Lupinus)

Dicecious: Literally, in two houses.
One-sexed ; male or female only, the
staminate (male) and _ pistillate
(female) flowers borne on different
individual plants. The flowers of
buffalo grass (Bulbilis), for exam-
ple, and of many ashes (Frazinus
spp.), maples (Acer spp.), and hol-
lies (Ilex spp.), are dicecious.

Discoid: Disklike, or lacking ray flow-
ers. Said of composites that have
only centers, or disk flowers, in the
flower heads, like the common nig-
gerhead (Rudbeckia occidentalis).

12 MISC. PUBLICATION 110, U.

Disk: An enlargement or prolongation
of the receptacle of a flower around
the base of the pistil; also, the head
of tubular flowers in composites.

Dissected: Cut deeply or divided into
numerous and usually narrow or fine
lobes or segments.

Distichous: Arranged in two ranks.
Thus, the leaves and floral bracts of
true grasses are distichous.

Divaricate: Diverging at a wide angle;
widely spreading.

Divided: Having the main divisions ex-
tending quite to the midrib or
rachis. A divided leaf is, therefore,
a compound leaf. (Figs. 12 and 13.)

Dm.: Decimeter(s), approximately 4
inches.

Dorsal: Upon or relating to the back
or outer surface of an organ.

Drupe: A simple, fleshy, or pulpy
fruit, the inner portion of the peri-
carp being hard and stony. A stone
fruit. The fruits of the peach, plum,
and cherry are familiar types of
drupes.

Ecesis: The adjustment of a plant toa
new habitat and its establishment
therein. The result of a successful
migration.

Ecology: That part of biology which
deals with the relationships of or-
ganisms to their respective habitats.
Literally, the science of home (habi-
tat). Plant ecology includes the
study of all the factors in the en-
vironment of the individual plant
and of groups of plants and the ef-
fects which these various factors
have on the forms of plants, their
life history, succession, etc.

E. g.: For example (Latin, exempli
gratia).

Elliptic: With the outline of an ellipse.

Emarginate: Notched or indented at
the apex. (Fig. 29, B.) Obcordate
is more deeply and retuse more shal-
lowly notched.

B Cc

FictrE 29.—Types of leaf tip: A,
BerURe B, emarginate; C, obcor-
ate

Embryo: The rudimentary, undevel-
oped plant (Sporophyte) in a seed.
resultant from the union of a stam-
inate (male) and a pistillate (fe-
male) cell; it ordinarily consists of a

S. DEPT. OF AGRICULTURE

radicle (embryo stem), one, two, or
more cotyledons (seed leaves), and
a plumule (minute bud). This last
indicates where the stem and next
leaf or leaves of the germinating
seedling will be developed.

Emergence: A growth outward from
beneath the epidermis. The prickles
of a rose stem, the ligule of a grass,
the corona of a milkweed or daffo-
dil blossom are examples of emer-
gences.

Emersed: Raised above the surface of
the water instead of floating on it;
said of certain aquatic plants, es-
pecially their leaves and stems.

Endemic: Indigenous or native in a re-
stricted locality; confined naturally
to a certain limited area or region.
Thus, Silene ingrami is endemic in
the Umpqua National Forest region
of southwestern Oregon.

Endocarp: The inner layer of a peri-
carp, or covering of a fruit. The
bony part of the stone of a cherry or
plum, for example, is botanically an
endocarp.

Ensiform: Sword shaped.

Entire: Without teeth, lobes, divisions,
or any marginal cutting; having a
smooth and uninterrupted, flowing
outline. (Fig. 30, A.)

A: BGC (Di «Eee

Ficurn 30.—Six types of leaf margin:

A, Entire; B, serrate; C, dentate; D,
undulate or repand; E, crenate; F,
incised

Ephemeral: Enduring for a day; eva-
nescent. Asthe ephemeral flowers of
many cacti, which wither the day
after blooming.

Epicarp: The outermost layer of a
fruit, especially in a 3-layered fruit
covering.

Epidermal: Of or pertaining to the
epidermis.

Epidermis: Literally overskin. The
thin outer cell layer in the higher
plants, roughly analogous to the
epidermis of animals, usually pig-
mented but mostly without chlor-
oplasts, and universally present in
leaves and herbaceous stems.

GLOSSARY OF BOTANICAL TERMS

Epigynous: Said of stamens or other
floral parts that are borne on the
ovary or adnate to it.

Epipetalous: Borne on the petals or
corolla. For example, the stamens
of gentians and mints are epipeta-
lous, being attached at their base to
the basal portion of the corolla.

Epiphyte: A plant which grows on an-
other plant but is not nourished by
it and hence not a parasite; an air
plant. Many lichens, mosses, ferns,
orchids, and other plants are
epiphytic.

Epiphytic: Of or pertaining to an
epiphyte; having the nature or
characteristics of an epiphyte.

Erose: Having an irregularly cut mar-
gin as if gnawed.

Kstipulate: Destitute of stipules.

Etiolation: Literally, blanching or yel-
lowing. Especially a paleness in
plants caused by absence or inade-
quacy of light, the green chloroplasts
being changed to leucoplasts. The
blanching of celery stalks for mar-
ket and the white sprouts of potato
tubers stored in a cellar are familiar
examples of etiolation. Etiolation,
or paleness of leafage or herbage,
may also be hereditary and is a
common phenomenon among races
or forms of plants in ornamental
cultivation; apparently such a con-
dition is “freakish,” having no
connection with light deficiency.

Kt seq.: And the following (Latin, et
sequentes).

Excurrent: Running out. For exam-
ple, a midrib of a leaf projecting
beyond the blade in a bristle is ex-
current. An excurrent trunk is one
that has one main longitudinal axis,
aS in a typical pine or fir tree.

Exocarp: The outer layer of a fruit
covering that is separable into two
or more layers; in a 3-layered fruit
covering, synonymous with epicarp.

Exotic: Foreign; not native; intro-
duced from another region. Op-
posed to indigenous.

Exserted: Thrust out of; protruding
from; projecting beyond the sur-
rounding organs; said especially of
pistils and stamens protruding from
their corolla.

Exsiccatz: Dried, pressed-plant speci-
mens; herbarium specimens; a her-
barium collection, especially a num-
bered suite or set of specimens by
a given collector or collectors.

Falcate: Sickle shaped.

Family: In systematic botany (tax-
onomy), a (usually natural) group
of closely related tribes and genera.
As, for example, the grass family,

13

the mint family, the rose family,
ete. Under modern rules of nomen-
clature names of plant families reg-
ularly end in -acere; as Poacer,
Menthacer, Rosacer, ete. In plant
ecology the term “family” is some-
times used to denote a portion of
a plant community composed en-
tirely of individual plants of the
same species; e. g., a pure stand
of fireweed on a burn is a family
in the ecological sense.

Farinaceous: Starchy, mealy.

Farinose: Clothed with a whitish,
mealy substance, as the lower leaf
surface of certain primroses (Prim-
ula).

Fascicle: A dense or close bundle or
cluster, especially of like organs
having a common _ source. The
leaves of white pine, for example.
are fasciculate.

Fasciculate: Arranged in fascicles.
Fertile: Fruit-producing or capable of
proper functioning in reproduction.

Ff.: Following.

Fibrovascular: Composed of fibrous
vessels, or channels. The fibrous
skeleton of roots, stems, and leaves
is composed of fibrovascular bun-
dles, of which phloem and xylem are
the two components.

Fide: By the authority of (Latin) ; in-
dicating the source of an identifica-
tion or other statement of fact;
same as the abbreviation “test.”
Sometimes abbreviated to fid.

Filament: The stalk of a stamen, on
which is borne the pollen sac or
anther.

Filiform: Threadlike; long, slender,
and cylindrical (terete).

Fimbriate: Fringed.

Fl.: Flora; flower(s), flowering.

Flabellate or Flabelliform:
shaped.

Flexuous: Bending gently in opposite
directions; slightly zigzag or wavy.

Floccose: Tufted woolly; with loose
tufts of woollike hairs.

Flora: The vegetation of a given re-
gion, or a botanical manual treating
thereof.

Floral: Of or pertaining to a flower, a
plant, or a flora.

Floral envelope: The parts of a flower
surrounding or investing the. essen-
tial reproductive organs (pistils and
stamens) ; the perianth.

Floret: A diminutive flower, especially
the readily detachable flowers of a
grass spikelet, consisting of the
lemma and its attendant palea, to-
gether with the essential floral or-
gans, the stamens and pistils. (Fig.
39; °B, ad, 0; 6, da.) -

Fan

14

Foliaceous: Leafy or leaflike, as the
foliaceous stipules of certain willows
(Salix) or the foliaceous involucre
of carrot (Daucus).

Follicle: A capsule or pod, matured
from a simple pistil, and opening
(dehiscent) along one (usually the
inner) suture. (Fig. 31.) lLark-
spur, monkshood, columbine, and
milkweed have follicular fruits.

Ficurn 31.—Follicle of an-
telope-horns (Asclepio-
dora decumbens): da,
Body of follicle, the pap-
pus-crowned seeds emerg-
ing from the dehiscent
apex; 6, peduncle

Follicular: Of or pertaining to a fol-
licle.

Forb: A weed in the range stockman’s
sense; a nongrasslike herb. (Greek,
phorbe, forage.)

Formation: One of the main ecological
groups into which vegetation is di-
vided, as (for example) grassland,
forest, and meadow; or hydrophytic,
mesophytic, and xerophytic forma-
tions.

Fr.: Fruit(s), fruiting.

Frond: The leaf of a fern.

Fruit: The ripened ovary of a seed
plant with its contents and various
envelopes. (Figs. 15, 31, 35, 42, and
64.) For example, a pea pod, a
grain of wheat, a huckleberry, and
a rose haw are all, botanically
speaking, fruits.

Frutescent: Somewhat shrubby, be-
coming a shrub (frutex). Often
used, though somewhat loosely, as
a synonym of fruticose, but it pref-
erably represents an intermediate
stage between suffruticose (under-
shrubby) and fruticose (shrubby).

Fruticose: Shrubby; having the char-
acteristics of a true shrub (frutex).

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

A term applicable to woody, bushy
plants of a considerable size, not at
all herbaceous (save for the season’s
growth) and not arborescent, or
treelike.

Fruticulose: Minutely shrubby; di-
munitive in size but otherwise hav-
ing the aspect and characteristics
of a true shrub, or fruticose plant.

Fugacious: Falling early; soon drop-
ping off and disappearing; fugitive;
Short-lived. Partly synonymous
with caducous and deciduous.

Fulvous: Dull yellow; yellow tinged
with brownish or grayish.

Funicle or funiculus: The (usually di-
minutive) stalk of a nonsessile ovule
or of the seed which ripens from it.

Fuscous: Dusky brown.

Fusiform: Spindle shaped; thickest in
the middle and tapering toward each
end.

Galea: A helmetlike or hoodlike en-
largement in a flower as, for exam-
ple, in the upper corolla lip of nu-
merous species of the figwort fam-
ily (Scrophulariacee). (Fig. 32, A,
g, and B, g.)

FiGURH 32.—Two types of galea: A,

Flower of fernleaf, or lousewort
(Pedicularis); 9g, the galea, or
hooded upper lip of ‘the corolla;
B, flower of monkshood (Aconi-
tum); g, the galea, or helmetlike
upper sepal

Galeate: Shaped like a galea, or hel-
met.

Gametophyte: A plant which bears sex
organs (stamens and pistils or, in
cryptogams, analogous organs).
The term is ordinarily used for the
sexual stage in plants which exhibit
alternation of generations. The
gametophyte of a fern is called the
prothallus. See “alternation of gen-
erations ” and “ sporophyte”.

Gamopetalous: Having the petals more
or less united. For example, the
corolla of a huckleberry, manzanita,
bluebell, or foxglove is gamopeta-
lous. The same as sympetalous.

GLOSSARY OF BOTANICAL TERMS

Gamophyllous: Having the leaves more
or less united. (Fig. 19.)

Gamosepalous: Having the sepals more
or less united.

Gen.: Genus, genera.

Generic: Of or pertaining to a genus.

Genetics: The science of plant or ani-
mal breeding. The branch of biol-
ogy dealing with heredity and all its
phases. ;

Geniculate: Kneelike; bent like a
knee; said of stems, the awns of
needle grass (Stipa), ete. (Fig. 38,
a.)

Genus (pl. -era): A group of related
species showing similar character-
istics and appearing to have a com-
mon ancestry. Thus, white pine,
yellow pine, sugar pine, and the va-
rious other pines are species com-
prised in the genus Pinus, which in
turn is included in the family
Pinacee.

Geotropism: The growth response of a
plant or its parts to gravity; said
especially of roots. Stems or other
aerial portions of the plant are some-
times said to exhibit negative geo-
tropism.

Gibbous: Humped or swollen on one
side; as, for example, the calyx of a
lupine.

Glabrate: Becoming glabrous, or nearly
So, in age.

Glabrous: Devoid of hairs or pubes-
ence; Smooth in the sense of absence
of all hairiness; literally bald.

Gland: A secreting or excretory part
or organ. Plant glands are usually
small and are often in the form of
glandular hairs.

Glandular: Pertaining to or possessing
glands. Viscid (sticky) plants are
familiar examples of glandularity.

Glans: The nut of an acorn, as distin-
guished from the cup.

Glaucous: Covered with a bluish or
whitish bloom, i. e., a sort of fine
waxen powder that may be removed
by friction or heat and tends more
or less to reduce transpiration, as in
a cabbage leaf or on a fresh plum.
Moderately pruinose.

Globose: Shaped like a globe; spherical
or approximately so and round in
cross section.

Glochidiate: Barb tipped; having the
apex furnished with twin, sharp,
small, reflexed points like a minia-
ture arrowhead. (Fig. 10, A.)

Glomerate: Crowded, congested, dense
(said especially of flower and fruit
clusters). Thus, if the rays, pedun-
cles, or branches of an umbel, cyme,
or corymb become shortened the in-
florescence tends to become glomer-

15

ate, and approaching capitate or
headlike.

Glumes: The two lowest chaffy bracts
of a grass spikelet, which are empty,
i. e., do not bear stamens or pistils
in their axils. (Figs. 39, A, a, b;
B, e, €, and 68, A,
g, h.) The lower
one is known as
the first glumeand
the upper one as
the second glume.
Chigrs5ed-and-c:
respectively. )

Glutinous: Gluelike
or gummy; said
especially of exu-
dations and
glands.

Grass: A member
of the natural bo-
tanical family

Poacee (Grami-
nee). Grasses
are ordinarily Ficurn 33.—Spike-

let of green nee-
dle grass (Stipa
viridula):a,
(Geniculate)
awn; 0, lemma;
c, second glume;
d, first glume

perennial or an-
nual herbs, but
certain species
(notably of the
Bamboo tribe)
have more or less
woody stems, some being arbores-
cent (treelike). The stems
(culmns) are rounded and mostly
hollow except at the joints (nodes).
The leaves are 2-ranked (distich-

ous) with a sheath and ligule.
(Hig 3, 21d. .4e>) The inflores-
cence is composed of _ spikelets.

(Figs. 33, 39, and 68.) The fruit is
a grain (caryopsis). Grasses are by
far the most valuable of all plant
families to man, including as they do
the grains, the canes, bamboos, and
a vast host of pasture, hay, and
other plants of outstanding economic
importance. Grasses comprise one
of the four main groups into which
our native forage plants are cus-
tomarily divided, the others being
grasslike plants, weeds, and browse.
Grasslike plants (the water grasses of
the stockman): Plants which re-
semble true grasses (Poacesz, or
Graminez) superficially but which
do not belong to that family and, as
a rule, are inferior thereto as forage
plants. One of the four main
groups into which our native forage
plants are ordinarily divided. The
most characteristic grasslike plants
are sedges (members of _ the
Cyperaces, or sedge family) and
rushes (genera Junecoides and Juncus
of the Juncaces, rush family). The
inflorescence of rushes has a 6-parted

16

flower (perianth), showing a close

relationship to lilies. Sedges have
3-ranked leaves and usually solid
stems which are often triangular in
eross section. The floral organs of
sedges are in the axils of 2-ranked or
spirally imbricated (i. e., more or
less overlapping) scales and, in the
case of the largest and most familiar
genus, Carex, the pistillate (female)
flower is enveloped in a sac called
the “perigynium.” Because the
majority of rushes and sedges grow
in wet sites, grasslike plants are
sometimes called “marsh grasses”
or “wet meadow grasses.” The
term “grasses”? for them, however,
is inaccurate and misleading.

Gymnosperm: Literally, naked seed.
A member of the Gymnosperms, one
of the two main groups into which
flowering, or seed-producing, plants
are customarily divided, the other
being the Angiospermz. Gym-
nosperms (to which pines and other
conifers belong) have the ovules and
seeds borne on a naked scale; an
enveloping ovary, aS well as a true
floral envelope (perianth) and
stigmas are wanting. Botanically
gymnosperms are a primitive and
relatively rather small group, but
economically they are of the highest
importance—to the forester probably
the most important of all.

Gynecandrous: A term applied to
those sedges (Carex spp.) which
have male and female flowers in
the same spike but the upper flowers
female, so that only the upper part
of the spike bears
fruit. The con-
verse of androgy-
nous.

Habit: Aspect; man-
ner of growth.

Habitat: The site or
environment which
a plant or plants
(as well as ani-
mals) natively oc-
cupy, and the
study of which is
the science of ecol-
ogy.

Halophyte: A plant
adapted to exist-
ence in a saline
environment, as

Ficurp 34.—Has-

greasewood, salt tate leat of
grass (Distichlis), (Riives aceto-
and the saltbushes sella)

(Atriplex spp.).
Hastate: Shaped like a spear or hal-
berd head, the basal lobes pointing

MISC. PUBLICATION 110, U.

S. DEPT. OF AGRICULTURE

outward and usually much shorter
than the blade. (Fig. 34.)

Haw: A hawthorn (Crataegus sp.) or,
more especially, its fruit; a small
pome, or hip, as in a rose. This
form of fruit is caused by the fleshy
enlargement of the hypanthium.

Head: A headlike formation, especially
a rounded, congested inflorescence
or seed cluster; the characteristic

' inflorescence of the aster, or com-
posite family (Asteracez, or Com-
posite). In a true head (capitu-
lum) the individual flowers are ses-
sile or nearly so.

Helicoid: Shaped like the spirally
coiled shell of a snail (Helix).
(Fig. 35.)

Heliotropism: Response in a plant to
the stimulus of sunlight; the turn-
ing or growth of the
aerial portion of a
plant to light ema-
nating from the sun
(Greek, helios); as
in the radicle and
plumule of the em-

bryo.

Hemi-: A prefix
(Greek) signifying

ee Z ae
erb: A phanerogam IGUEN Res
(flowering plant), Beal reas
the aerial portion falfa

of whose stem is

destitute of woody tissue and per-
ishes when flowers and fruit are
matured. An herb may have an an-
nual, biennial, or perennial root,
but the aerial stem is ordinarily
annual; when a stem survives into
the second or ensuing seasons there
is naturally a tendency for woody
tissue to form and for the transition
to shrub or tree status to ensue.

Herbaceous: Of or pertaining to herbs;
having the characteristics of an herb
and free from woody tissue.

Hermaphrodite: A word (both noun
and adjective) used to describe an
individual having the organs, char-
acteristics, qualities, or attributes
of both sexes. Said specifically, in
botany, of a perfect flower, i. e., one
containing both pistils and stamens.

Heterogenesis: Same as alternation of
generations.

Hexamerous: Having the parts in
sixes (Greek, hex, six, -+ meros,
part).

Hilum: The scar on the surface of a
seed which shows the place of de-
tachment of the matured ovule from
its base or seed stalk.

Hirsute: Hairy with rather coarse,
stiffish, straight, beardlike hairs.

GLOSSARY OF BOTANICAL TERMS

Hirtellous: Minutely hirsute.

Hispid: Bristly ; beset with stiff, rough,
bristlelike hairs.

Hispidulous: Minutely hispid.

Histology: Microscopic anatomy; the
science or study, by the use of a
microscope, of the more minute
structures of plants and animals.

Holotype: The sole specimen on which
a species is based, when that speci-
men was: (1) The only one ob-
served by the author of the species
at the time he prepared the original
description of the species; (2) the
one definitely and exclusively cho-
sen or indicated by the author as
the type of the species; and (3) the
one which alone has served to es-
tablish an original description (pro-
tograph) given or cited.

Homonym: The same name for a dif-
ferent plant; a specific or generic
name untenable because preoccupied.
For example, the generic name Pinus
would be a homonym, and unten-
able, if applicable to any other group
of plants than the pines.

Hortus siccus: A herbarium; literally,
a dry garden.

Host: The organism from which a
parasite derives its sustenance.
Thus, clover is a frequent host for
dodder.

Hyaline: Thin and translucent.

Hybrid: The progeny of a male of one
race, variety, subspecies, species, or
sometimes genus, and a female of an-
other. In general hybridization is
confined. to congeners unless a nar-
row generic concept is held. Many
authorities prefer to limit the term
hybrid to a cross between different
species, crosses between races being
termed half-breeds, while those be-
tween subspecies, varieties, and
forms, and sometimes between races
also, are known as_ crossbreeds.
Where the ancestry is mixed the
term mongrel is often applied. Hy-
bridization is usually indicated by
the cross mark (xX).

Hydrophyte: A plant that grows in
water or in wet or Saturated Soils,
as distinguished from its opposite,
xerophyte, and the intermediate
mesophyte.

Hypanthium: The base of a flower;
specifically, an enlargement or elon-
gation of the floral axis below the
calyx, commonly inclosing the ovary
and pistils. An apple or rose haw
is an enlarged, fleshy hypanthium.

Hypha (pl. -@): A threadlike compo-
nent of a fungus mycelium, length-
ening by growth from the tip and

892075 O- 50-3

17

often showing transverse partitions.
See mycelium.

Hypogynous: Said of stamens or other
floral parts that are borne at the
base of the ovary or below it.

Hyponym: An improperly published
botanical name (such, for example,
as a nomen nudum, or mere name,
without any description or figure)
and which, because of its indefi-
niteness and uncertainty, can have
no validity or standing under the
codes. For example, Aragallus is an
older name than Oxytropis but is
rejected aS a hyponym.

I. e.: That is (Latin, id est).

Imbricate(d): Partially overlapping
like shingles or tiles on qa roof as, for
example, the involucral bracts (phyl-
laries) of a thistle. (Fig. 36, B, a.)

Immersed: A term used for aquatic
plants or their parts that are en-
tirely submerged.

Imperfect: Wanting either stamens or
pistils; unisexual. Said of flowers.

Incised: Having the margins cut into
sharp, deep, irregular incisions or
teeth. (Fig. 30, F.)

Included: Inclosed in and not protrud-
ing from the surrounding organs.
For example, the stamens and style
of most bluebell (Mertensia spp.)
blossoms are included.

Indehiscent: Not spontaneously split-
ting open or dehiscing.

Indeterminate: The (more usual) type
of inflorescence in which the flower
buds are axillary or lateral rather
than terminal (determinate) so that
the main stem may continue its
growth. (Fig. 22.)

Indigenous: Native. Thus, Achillea
lanulosa is the common indigenous
yarrow of the western United
States, while A. millefolium is the
common yarrow introduced from the
Old World.

Indurated: Hardened and stiffened.

Indusium (pl. -ia) : The thin, scalelike
outgrowth of the leaf of a fern
forming a covering for the imma-
ture sori, or fruiting dots.

Inferior: Being in a lower position or
having the base attached below some
other organ. Said especially of the
ovary when adnate to the hypan-
thium and having the calyx lobes
and other floral envelopes (if any)
above it.

Inflorescence: The flowering part of a
plant, and especiaily the mode of
its arrangement.

Infra-: A prefix signifying below.

Innovation: An offshoot from the main
stem, which frequently becomes es-

18

tablished as a new, independent
plant, as in mosses; an incomplete
young shoot, aS in grasses.

Internodes: The portions of a stem be-
tween the nodes, or joints

Interrupted: Not continuous; not wuni-
form, for example, in density, as an
interrupted spike, i. e., a spike which
has the flowers in some place or
places smaller or fewer in number
than elsewhere.

Introduction: An exotic plant intro-
duced by man or other agency from
its native region to another. Thus
in the United States wheat and the
common dandelion are introductions
from the Old World.

Introrse: Turned in; facing inward.
Said, for example, of an anther at-
tached on the inner side of its fila-
ment and facing toward the inside
of the flower.

Involucel: A secondary involucre; said
especially of the whorl of bractlets
subtending the umbellets of many
umbellifers. (Fig. 36, C, ¢.)

Involucre: A whorl of distinct or
united bracts or leaves subtending

A, Flowering
dogwood (Cornus florida) ; @, a, a, G,
four petaloid involucral bracts form-

Ficurb 36.—Involucres:

ing an involucre about the central
flower cluster; B, part of flower head
of a thistle (Cirsium sp.) ; @, involu-
ere, composed of involucral bracts
(phyllaries) in numerous rows; C,
umbel of carrot (Daucus sp.) 5 a, a, a,
@, a, pinnatifidly lobed involucral
bracts, forming involucre; 0, Bb, rays,
branches, or peduncles of umbel; e,
involucel, composed of involucellar
bracts; d, umbellet

a fiower or flower cluster. The
petallike bracts of a flowering dog-

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

wood (Cornus spp.) flower cluster
are a familiar example of involucre.
(Fig. 36, A.) In an umbellifer the
involucre subtends the umbel. (Fig.
36, C, a.) In a composite the invol-
ucre is the usually cup-shaped en-
velope of encircling, often imbri-
cated (partially overlapping) bracts
subtending the flower head. (Fig.
36, B, a.) The cup, or cupule, of an
acorn is also sometimes referred to
as the involucre. .

Involute: Inrolled; i. e, with both
edges rolled in toward the middle
(as a leaf) each edge presenting a
spiral appearance in cross section.

Isotype: A duplicate of a type speci-
men (holotype). A term introduced
by F. W. Pennell of the Philadel-
phia Academy of Natural Sciences,
See paratype and cotype.

Katabolism: An alternate spelling for
catabolism.

Keel: A projecting ridge on a surface,
like the keel of a boat. When a
grass glume or lemma is more or
less compressed and boatlike, its
midrib, if projecting, is called a keel.
The two, often more or less joined,
boatlike, forward petals of a pea
family corolla are also known as
the keel. (Fig. 48, ec.)

Keeled: Provided with a keel or keels,

Labiate: Lipped. A plant of the mint
family (Menthacez, or Labiate),

whose members
have lipped, or
labiate, corollas.

Lacerate(d): Deep-
ly and irregularly
cut along the
edges.

Laciniate: Narrowly
incised or Slashed ;
having the margin
cut into deep nar-
row lobes.

Lamina: A leaf
blade (fig. 37, b);
the broader por-
tion of a leaf or of
a clawed petal.

Lanate: Woolly, with
dense, long, soft,
more or less entan-
gled, butnot matted (tomentose) hairs.

Lanceolate: Lance shaped; several
times longer than broad and taper-
ing from the relatively narrow base
to the apex. (Fig. 38, B.)

Lanuginous: Downy; beset with fine
Soft hairs; pubescent.

Lateral: Of or pertaining to a side of
an organism or of its parts.

Latex (pl. -tices): A more or less
milky and opaque, usually gummy,

FIGURE 37.—Parts

of a grass leaf
and stem: a,
Culm; 6, blade
(or lamina) ; ¢,
ligule ; d, sheath

GLOSSARY OF BOTANICAL TERMS

Sometimes oily or waxen exudation

from a plant. The milky juices of
sumacs, lettuce, milkweeds, spurges,

A B C D

Ficgurp 388.—Four common leaf out-
lines (see also Figures 34, 43, 44,
62, 638, and 73); A, Linear; B, lan-
Coole; C, oblanceolate; D, spatu-
ate

and polygalas, the resin of a pine,
mastic of a pistache, and the caout-
chouce or crude rubber of the rubber
tree are familiar examples of latices.

L. c., or loc. cit.: In the place cited
(Latin, loco citato).

Leaflet: A single division of a com-
pound leaf. Ashes, boxelders, clo-
vers, locos, lupines, meadowrues,
mesquite, and polemoniums are fa-
miliar illustrations.of plants having
leafiets.

Leg.: Collected; also, sometimes, ex-
plains or interprets (Latin, legit).
Legume: A simple pod, 1-carpelled and
usually dry, splitting (dehiscing)
along the back into two valves or
parts; the fruit of any leguminous
plant, i. e., a member of the pea
family (Fabacez) or families close-
ly related thereto (Cesalpiniacea,
ete.) ; also a plant belonging to these
leguminous families or subfamilies.

Leguminous: Of or pertaining to the
natural family Fabacee (or Legu-
minoss#), to which the cultivated
peas and beans belong; having the
characteristics of a plant of the pea,
or legume, family.

Lemmas: The so-called “ flowering
glumes” of grasses (fig. 39, A, c and
B, d); the chaffy bracts, which, to-
gether with the paleas, inclose the
stamens and pistils or essential
floral organs. A 1-flowered grass
spikelet has, of course, one lemma
only, a 2-flowered spikelet has two
lemmas, and so on.

Lenticular: Resembling a lens in shape,
appearance, or characteristics.

Lepidote: Covered with scurfy scales.
The buffaloberries (Lepargyrea
spp.) and silverberry (Hlezagnus)

19

furnish familiar examples of lepi-
dote foliage.

Ligneous: Woody.

Ligulate: Provided with a ligule; of or
pertaining to a ligule. Occasionally
also used aS a Synonym of lorate.

Ligule: The projecting, usually tongue-
like, membranous end of the lining
of the leaf sheath, seen at the base
of the leaf blade, between it and the
stalk, and a very characteristic fea-
ture of the grass family. (Fig. 37,
ec.) The ligule is quite constant in
a given species and is often an im-
portant means of distinguishing
grasses; sometimes it is reduced to
a mere fringe of hairs or to a hard-
ened ring. Some botanists call the
rayS of composite flower heads
ligules.

Limb: Literally, a border or edge; spe-
cifically, a free portion, especially
the upper, spreading part of a gamo-
petalous corolla, in distinction to the
tube, or tubular, basal portion.

Linear: Linelike, narrow and flat, with
the margins parallel. (Fig. 38, A.)
Most grass leaves are linear or
nearly so,

Ficurn 39.—A, Incomplete spikelet of

blue grama (Bouteloua gracilis): a,
first glume; 6, second glume; c, lemma ;
B, spikelet of timothy (Phleum. pra-
tense) ; a, 6, c, ad, floret; a, anthers; 0,
filaments; c¢, stigmas (plumose); d,
lemma; e, glumes (aristate and ciliate)

Lip: The upper or the lower division
of a 2-lipped (bilabiate) corolla or
calyx; the peculiar, enlarged, appar-
ently lower (but technically upper)

20

petal in the orchid family (Orchi-
dace).
Lobed: Incised, but with rounded

rather than sharp margins, and not
deeper than about halfway between
the outer edge and the blade center
—usually less; said of leaves, petals,
(Fig. 40.)

ete.

B

FicurRE 40.—Lobed leaves: A, Pal-
mately lobed leaf, as in floating
pennywort ,(Hydrocotyle ranuncu-
loides) ; B, pinnately lobed leaf, as
in certain oaks (Quercus spp.)

Lodicule: One of two (occasionally
three) small hyaline scales, repre-
senting the corolla, found in the
florets of most grasses inside the
lemma and palea and subtending the
floral organs (pistil and stamens).

Loment: A legume, or pod, constricted
between the seeds.

Lorate: Shaped like a strap or thong
(lorum).

Lunate: Crescent shaped (from luna,
moon).

Lyrate: Lyre shaped; more or less
spatulate in outline but with two
or more small basal lobes.

M.: Meter(s), approximately 39 inches,
or about 314 feet.

Major quadrat: A square sample plot
of vegetation larger than the usual
1 square meter quadrat unit.

Marcescent: Withering but not decidu-
ous, aS shown, for example, in the
dried persistent leaves in certain
buneh-grass tufts.

Membranaceous: Thin and translucent,
resembling a membrane; membran-
ous.

Membranous: Of or pertaining to a

membrane;
branaceous.
Mericarp: A division of a compound
fruit, especially one of the separate
1-seeded carpels of a sSchizocarp or
one of the dry pendulous halves of a

membranelike; - mem-

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

eremocarp, or fruit of the umbellifer
(parsnip) family. Literally, part
fruit.

Meristem: Growing tissue; embryonic
or undifferentiated portions of a
plant whose cells are capable of ac-
tive division.

Meristematic:
meristem.

-merous: A suffix (Greek, meros, part)
indicating division into parts. For
example, a typical 4-merous or tetra-
merous flower has 4 sepals, 4 petals,
4 stamens, and a 4-celled ovary.

Mesocarp: The middle layer of a 3-
layered pericarp (outer covering of
a fruit). Ina fleshy fruit, the same
as sarcocarp.

Mesophyte: A plant that grows under
medium or average moisture Condi-
tions; neither an aquatic (hydro-
phyte) nor a desert species (xero-
phyte). The vast majority of plants
growing in the United States are
mesophytes.

Metabolic: Of or pertaining to me-
tabolism.

Metabolism: The life processes of
plants as Summed up in the chemical
and physical changes involved in
their growth, reproduction, and de-
cay. Metabolism may be construc-
tive (anabolism) or destructive
(catabolism).

Micro-: A prefix (Greek) signifying
small, or minute. It has in general
a rather more intensive significance
than the Latin prefix parvi-, and is
preferably applied to microscopic ob-
jects and parts.

Micropyle: The minute opening of an
ovule through which the pollen tube
enters and fertilization is accom-
plished. In the seed the micropyle
is closed and usually persists as a
small sear.

Migrant: That which migrates or has
migrated; a plant which, by seed or
other means, invades a new area or
habitat. As a tree migrant in a
meadow.

Migration: Invasion, or the movement
of plants into new areas.

Milacre: A plot onethousandth part
of an acre in extent, one-tenth of a
chain or 6.6 feet square; containing
43.56 square feet.

Mm.: Millimeter(s), approximately
one twenty-fifth of an inch.

Monadelphous: Literally in one broth-
erhood; said of Stamens where all
in a flower are united by their fila-
ments into a single tubelike or col-
umnlike cluster.

Moniliform: Resembling a string of
beads, as the moniliform roots

Of or pertaining to

GLOSSARY OF BOTANICAL TERMS 21

(corms) of Cogswellia farinosa or
the moniliform pods of certain spe-
cies of corydalis; torose in an ex-
treme degree.

Mono-: A prefix (Greek) signifying

one.

Monocotyledon: A plant having but
one cotyledon, or seed leaf, as a
grass, sedge, rush, lily, palm, etc.
The monocotyledons are one of the
two main divisions of angiosperms,
the other being the dicotyledons.
Moneecious: Literally, in one house.
Having the flowers differentiated as
to sex, the staminate (male) and
pistillate (female) flowers in sepa-
rate inflorescences, but borne on
the same individual plant, as dis-
tinct from one-sexed, or dicecious
plants, and hermaphrodites, or
plants having perfect flowers (con-
taining both pistils and stamens).
Many of our most important Ameri-
can trees, such as pines, oaks, and
birches, are moneecious.

Monostichous: Borne on one side of an

axis; 1-sided, as the inflorescence of
blue grama. Same as secund.

Morphology: The science of form and

structure. Plant morphology is
Sometimes called structural botany;
it deals with the forms of plants
and of their organs, their anatomy
(gross morphology), relationships,
and development. Systematic bot-
any (taxonomy) is based on mor-
phology. Physiology differs in that
it deals with the functions, life proc-
esses, and activities of plants rather
than with form and structure. Cy-
tology (cell science) and histology
(microscopic anatomy) deal with
the microscopic morphology of the
plant.

Mucro: A sharp, straight point, espe

cially if abrupt and short.

NEN VE
NZ
NIG
oN

A Be GC

FicurB 41.—Three
types of terminal
pointing, as in
leaves, leaflets, pet-
als, and sepals; A,

ucronate; B,
apiculate; C, cus-
pidate

Mucronate: Ending in a mucro, or
sharp point, especially if the tip is
abrupt, short, and small. (Fig. 41,
A.)

Multi-: A prefix (Latin) signifying
many or numerous.

Muricate: Rough with short hard
prominences. (Fig. 42.)

FicureE 42.— Muri-
cate nutlet (seed),
as in certain spe-
cies of Amsinckia
and other western
annuals of the
borage family

Muticous: Awnless, pointless, or un-
armed. Literally, docked.

Mycelium: The interwoven hyphal tis-
sue composing the vegetative thal-
lus, or body, of a higher fungus and
from which the sporophores, or re-
productive parts, are produced. In
mushrooms it is the cobwebby
“spawn” of the seedsman, consist-
ing of an entangled subterranean
mass of hyphe, or filaments.

Mycorrhiza: Literally, fungus root. A
Symbiotie (or possibly sometimes
parasitic) relationship or associa-
tion between a fungus and the root
of some higher plant. Beeches,
oaks, birches, conifers, orchids, and
heaths are among the plants which
provide familiar examples of this
condition. Mycorrhizas are either:
(1) -Eetotrophic, or external, the
fungal hyphe, or filaments, forming
a mass about the root tips, or (2)
endotrophie, or internal, the myce-
lium of the fungus occupying the
parenchyma of the roots of the
flowering plant.

N. s., or n. ser.: New series; n. s. is
also occasionally used for new
species.

N. sp.: New species; also abbreviated
Sp. nov., nov. Sp., and occasionally

Dees:

Nanism: Dwarfishness or dwarfing; a
depauperate state of a plant, such
as at alpine elevations. Some writ-
ers, however, prefer to distinguish
between nanism and depauperation,
using the former term for plants
whose diminutive size is hereditary,
depauperate plants being starved
but nonhereditary forms dwarfed by
unfavorable growth conditions.

Nat.: Natural, nature.

Nectar: The sugary exudation of cer-
tain flower glands (nectaries), at-

22

tractive to insects, to which the
floral perfume is largely or some-
times wholly due, and from which
bees derive honey.

Nectariferous: Nectar bearing or pro-
ducing; secreting nectar, aS a nec-
tary.

Nectary: A gland, usually situated at
or near the base of a corolla or
perianth, or one of its parts, which
secretes nectar.

Nerve: A name for ribs or veins, when
unbranched and approximately par-
allel, applied especially in the case
of leaves and the chaffy bracts
(glumes, lemmas, and paleas) of
grass flowers. The terms “nerve”
and “ vein” in botany, of course, are
wholly different in meaning from
the same terms used in zoology and
human anatomy.

Nerved: Provided with nerves, as a
1-nerved glume.

Node: A joint or knot. Said especially
of stems, whose nodes or joints are
enlarged, often dark colored, and are
the points whence leaves often
spring.

Nom. nov.: New name (Latin, nomen
novum), i. @., a name, hitherto un-
published, substituted for one in
general use but ascertained to be
untenable.

Nom. nud.: See nomen nudum.

Nomen conservandum: Literally, a
conserved name. A name retained
in Latin plant (or animal) nomen-
clature regardless of priority. Nom-
ina conservanda are rejected by the
American Code of Botanical Nomen-
clature (used by the United States
Department of Agriculture, New
York Botanical Garden, Leland
Stanford University, etc.) but are
admitted under the International
Code (used in Europe, the Gray
Herbarium of Harvard University,
the University of California, etc.)
Thus, under the Paris (Interna-
tional) Code, Glyceria R. Brown
(1810), although published 47 years
after Panicularia Heister (1763), is
retained for the manna grasses as
a nomen conservandum. Nomina
conservanda usually have a history
behind them of long usage (possibly
pre-Linnaean), acceptance by the
great botanical figures of the past,
better and fuller publication, ques-
tions of taste and propriety, ete.

Nomen nudum (pl. -ina nuda) : Liter-
ally, a naked name, i. @., a name
only; a plant name published with-
out any description or figure, and
hence which can not be tied in with

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

assurance to any plant or plant

group. Nomina nuda are very prop-

erly rejected by all codes. For ex-
ample, in the Flora of Washington

is published, without description, a

new subspecies of mistletoe, Razowm-

ofskya douglasii laricis; such a name
is a nomen nudum. Nomen seminu-

dum is a term used to designate a

name published with only a word or

two, or a description otherwise
wholly inadequate.

Nucleus: The organ of a plant or ani-
mal cell which is essential in ana-
bolism, growth, reproduction, and
heredity.

Nut: A nonsplitting (indehiscent) 1-
seeded fruit, with hard woody shell
(pericarp), and developed from an
inferior, several to many carpelled
ovary. In popular usage almonds,
peanuts, and Brazil nuts are nuts,
but they are not so botanically; an
almond is a drupe (close akin to a
peach) ; a peanut, a legume; while
the fruit of the Brazil-nut tree (Ber-
tholletia excelsa@) is a sort of large,
woody-shelled capsule (pyxis) con-
taining nutlike seeds.

Nutlet: A small nut or nutlike fruit or
seed. (Fig. 42.) For example, the
fruits of the borage, verbena, and
mint families are nutlets.

Nyctitropism: The tendency of some
leaves and other plant organs to
assume certain positions at night
or in darkness; familiar examples
are seen in the drooping leaflets of
clovers and locusts as night ap-
proaches.

Ob-: A prefix (Latin) signifying in an
opposite direction or other reversion.

Obcordate: Reverse heart shaped;
with the broader, notched ends for-
wards or upper-
most, as in the
leaflets of oxalis
and white clover.
(Fig. 438.)

Oblanceolate: Re-
verse lance ;
shaped (lanceo- %:
late); with the SO
narrowed, taper-
ing part down- 7
ward, and the
broader end fore-

a (Fig. 38, eae eas
Oblique: Unequal sided; slanting.
Oblong: About two to four times longer

than broad, and with the _ sides,

though gently rounded, approxi-

mately parallel. (Fig. 44, A.)

GLOSSARY OF BOTANICAL TERMS

Obovate: Reverse egg shaped (ovate) ;
in longitudinal section, with the
broader end forward or uppermost.
(Fig. 44, C.) Used of flat or 2-
dimensional figures.

Ficgurnh 44.—Three common shapes or
outlines of leaves (see also Figures
84, 38, 43, 62, 63, and 73) : A, Oblong ;
B, ovate; C, obovate

Obovoid: Reverse ovoid, or egg-shaped,
with the broader end foremost or
uppermost. Used of solid, or 3-di-
mensional, objects.

Obtuse: Blunt or rounded at the tip;
not sharply pointed ;'as in the ovate
leaf shown in Figure 44, B.

Ochroleucous: Yellowish white; cream
colored.

Ocrex: Literally, boots; a term ap-
plied to the characteristic membra-
nous, sheathing, united stipules of
the buckwheat family (Polygo-
nace).

Offset: A form of short runner; a
short basal prostrate lateral branch
which roots at the tip and eventually
tends to produce a Separate indi-
vidual plant.

Ontogeny: The life history or develop-
ment of an individual plant or ani-
mal, as opposed to phylogeny, or the
study of a group.

Odspore: In nonflowering plants (cryp-
togams), where alternation of gen-
eration occurs, the egg cell
(odsphere), after it is sexually ferti-
lized, develops a hardened outer wall
of cellulose and (usually) goes into
a resting stage (the odspore). From
it germinates the sporophyte, which
ig the (usually more conspicuous)
plant which produces asexual spores.

Op. cit.: Work already cited (Latin,
opere citato).

Opposite: Arranged in pairs, at an
angle of 180°; i. e., on opposite sides
of a stem. Said especially of leaves
and branches. The leaflets shown in,
Figure 55, B, are opposite. See
alternate and whorled. Leaf and
branch arrangement are among the

fundamental ways of distinguishing
plants vegetatively, L e., apart from
sexual characters (flowers and
fruit).

Orbicular, or orbiculate: More pre-
cisely, a term applicable to 3-dimen-
sional, or solid objects and synony-
mous with spherical or globose; in
botany, however, through long usage,
usually applied to 2-dimensional
(plane) objects circular in outline
or nearly So, as an orbicular (orbicu-
late) leaf.

Organ: A member; a plant (or ani-
mal) part having a special function
or functions; e. g., a root, a leaf, a
pistil, a stamen.

Oval: Broadly elliptical Some au-
thors, however, have used oval as a
Synonym of ovate.

Ovary: The organ (fig. 45, @) in which
are borne the ovules, or rudimentary
seeds; usually a basal cavity in the

DIr'stil.- Itsis
found only in a
angiosperms.

Ovate: Having
the outline of a b
hen’s egg in
longitudinal Cc
section, with Cc
the broader end d
downward or
inward. (Fig.
44,B.) Aterm fFeurn 45.—- Pistil,
used in de- or female floral
scribing 2-di- pace sone eee
mensional, or bit (such as a

plane, objects
such as a leaf.
Ovoid: Shaped
like a hen’s egg
and with the
broader end downward or innermost.
A term used in describing solid, or
3-dimensional parts, such as a fruit.
Ovule: A rudimentary seed occurring
in the ovary. (Fig. 45, c.)
Palatability: An expression of the rela-
tive relish with which food is con-
sumed. Specifically, in Forest Serv-
ice range management, reconnais-
sance, and research, the degree to
which the herbage within easy reach
of livestock is grazed when a range
is properly utilized under the best
practicable range management. The
percentage of the readily accessible
herbage of a species that is grazed
when the range is properly utilized
determines the palatability of the
species.
Palea: A chaffy bract; specifically (1)
the chaffy bract which often occurs
in a grass floret opposite the lemma

melon): a, Lobed
stigma; b, style;
c, ovules (borne on
axile placenta) in
ad, ovary

24

and which, together with the lemma
and lodicules, incloses the stamens
and pistils and later the grain; (2)
one of the chaffy bracts on the stipes
of certain ferns; (3) a chaffy bract
on the receptacle or in the pappus
of some composites. Same as palet.

Palet: See Palea.

Palmate: Digitate. The term refers to
organs (e. g., leaflets) which are

FicurE 46.—Palmate
leaf, as in cinque-
foil (Potentilla sp.)

radiately lobed or divided, suggest-
ing the outspread fingers of the
hand; as, for example, the leaflets
of cinquefoil, clover, lupine, and
horsechestnut or buckeye. (Fig. 46.)
A trifoliolate leaf, as in clover, is
3-palmate or digitate; a quinquefoli-
olate leaf, as in cinquefoil (Poten-
tilla) is 5-palmate or digitate.
Panicle: A compound raceme; a com-
pound, more or less open inflores-

ZO
C)
, =O
(a Z
®
ON ye
AY Ww

Ficurp 47.—A panicle

cence in which the lower branches
are typically longer and blossom
earlier than the upper branches.
(Fig. 47.) The term is sometimes

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

loosely applied to any irregular com-
pound inflorescence.

Paniculate: Panicled;. arranged in
panicles; having the form or char-
acteristics of a panicle, as the panic-
ulate inflorescence of Kentucky blue-
grass.

Papilionaceous: Literally, butterflylike.
A term used to describe the shape
of the characteristic corolla of the
pea family. (Fig. 48.) See keel,
standard, and wing.

Papilla: A diminutive nipplelike or
pimplelike protuberance. ‘Typical
papillz may be seen, for example,
on the leaves of certain mertensias,
the . seeds of certain catchflies
(Silene spp.) and spurges.

Papillate: Beset with papilla.

Papillose: Same as papillate.

48. — Papiliona-
corolla, as in

FIGURE
ceous
sweet pea (Lathyrus
odoratus) and _ other
leguminous plants: ad,
Banner or standard;
b, wing petal; c, keel;
d, pedicel

Pappus: Thistledown; the peculiar
calyx limb of composites (Astera-
cee), etc., surmounting the achene,
or fruit, commonly bristlelike, awn-
like, or feathery, and an instrument
of seed dispersion by wind, animals,
etc. The feathery pappus of a dan-
delion seed is a familiar illustration.
(Fig. 49, a.)

Parasite: An organism (plant or ani-
mal) which derives its sustenance
from another. Thus, mistletoes are
parasites of oaks, pines, and other
woody plants.

Paratype: In general, one of the origi-
nal series of specimens in which the
type specimen was collected. Ac-
cording to some authors this defini-
tion applies only where the type

GLOSSARY OF BOTANICAL TERMS

specimen is a holotype (q. v.), thus
being equivalent to isotype. See
also cotype.

Ficgurn 49.—Achene, or
fruit, of the common
dandelion (Leontodon
tarazacum): a, Pap-
pus; 8, beak; c, body
of the achene

Parenchyma: Thin-walled, soft cell tis-
sue. One of the two primary types
of plant tissues, of which the other
is termed proSenchyma. Parenchy-
ma usually occurs in the form of
cubical or polygonal cells; familiar
examples are seen in stem pith, most
leaves (except the veins and mid-
rib), fruit pulp, ete.

Parietal: Literally, of or pertaining to
a wall (paries) or wall-like part;
hence, wall-borne. Applied specifi-

cally, in botany, to
a placenta or ovule
that is attached to
the wall of the
ovary.

Parted: Not quite di-
vided. Said of sim-
ple leaves that are
incised almost to
the midrib or blade
base, and so are
not quite com-
pound. (Fig. 50.)

Pathology: The sci-
ence which treats
of diseased or mor-
bidconditions.

1 Plant pathology

l) deals with plant
diseases, their
causes, effects, and
treatment or cure.

Pectinate: Comblike;
arranged or di-

vided like the teeth of a comb

(Latin, pecten).

FIGURB 50.—A
parted leaf, as
in certain spe-
cies of oak

25

Pedate: Palmately cleft or parted but
with the main divisions having a
common stalk, i. e., the primary divi-
sions twice or more cleft or parted.
Thus, the leaves of birdsfoot violet
(Viola pedata) and of dragonroot
(Arisema dracontium) are pedate.
(Fig. 51.)

(——>S> IA
A (SS
B

FiGURH 51.—Pedate leaf, as in (A)
birdsfoot violet (Viola pedata) and
(B) dragonroot (Arisema dracontium)

Pedicel: In an inflorescence consisting
of more than one flower, the foot-
stalk or stem of an individual flower
or fruit. (Fig. 48, d.)

Pedicellate: Provided with a pedicel,
or stalk; not sessile. Said of indi-
vidual flowers or florets.

Peduncle: The stalk of a flower cluster
or of an inflorescence consisting of
but one flower. See pedicel.

Pedunculate: Provided with a peduncle.

Peltate: Shield shaped; a peltate leaf,
as in nasturtium, has the petiole at-
tached somewhere near the center of
the blade. (Fig. 52.)

FIGURE 52.—Peltate leaf, ag in
the common nasturtium

Pendulous: Hanging down; suspended
from above; pendent; drooping.

Pentamerous: Having the parts in fives.

Pepo: The characteristic indehiscent
fruit of the gourd family (Cucurbi-
tacee), such aS a cucumber, musk-
melon, pumpkin, or squash. It dif-
fers from a berry chiefly in having
a hard, more or less thickened rind
(pericarp).

26

Perennial: Lasting for three or more
years; said especially of herbaceous
plants that are neither annual nor
biennial. A perennial plant. Fre-
quently expressed by the symbol 2/.

Perfect: Having both stamens and pis-
til(s); said of flowers. The great
majority of flowers are perfect.

Perfoliate: Literally through the leaf;
refers to leaves or stipules whose
clasping bases are united beyond,
and as if pierced by, the stem.
(Fig. 53.)

Perianth: The floral envelope, consist-
ing of the calyx and corolla, how-
ever incomplete or modified. Used
particularly for plants, like lilies, in
which the calyx and corolla can not
readily be distinguished.

53.—Perfoli-
ate leaf, as in thor-

FIGURE
oughwort spring-

beauty (Claytonia
perfoliata)

Pericarp: The outer covering, varying
greatly in texture and thickness, of
a fruit and corresponding. to the
outer walls of the ovary from which
it was fashioned. In a pod the peri-
carp is mostly thin and dry; in a
drupe or berry, thick and fleshy; in
a nut, bonelike in texture. The
pericarp often consists of two lay-
ers (endocarp and exocarp) or of
three layers (endocarp, mesocarp,
and epicarp). In a peach or plum,
for instance, the bony stone sur-
rounding the seed is the endocarp,
the edible fleshy portion is the meso-
carp, or sareocarp, while the thin
outermost rind, or peel, is the epi-
carp.

Perigynium (pl. -ia): The saclike
organ which completely incloses the
ovary, and at maturity the achene
(seed), in sedges of the genus
Carex; the perigynium is usually

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

more or less beaked and often 2-
toothed at apex and affords some
of the best characters for distin-
St iss eines
species of this
difficult genus.
(Fig. 54, A.)

Perigynous: Sit-
uated around
the ovary ; said
of petals and
stamens when
borne on the
calyx, as, for
example, in the
rose family
(Rosace®@).
Literally,
around (the) woman, i. e., encircling
the pistil.

Persistent: Remaining attached, in-
stead of falling away, at the time
such parts ordinarily drop off; said
of evergreen leaves, calyces remain-
ing at fruiting time, ete.

Petal: Typically one of the separate,
usually colored, modified leaves of a
choripetalous corolla and making up
the inner and upper series of the
floral envelope (perianth) parts.
Also, though less precisely, one of
the more or less fused divisions of
a gamopetalous corolla (as the five
united petals of a manzanita co-
rolla).

Petaloid: Petallike, as the petaloid in-
volucral bracts of the flowering dog-
woods (Cornus florida and C. nut-
tallit).

Petiolate: Furnished with a petiole, or
leafstalk (said of leaves).

Petiole: A leafstalk, whereby the blade
of a leaf is attached to the plant
stem.

Petiolulate: Furnished with a petiolule
(said of leaflets).

Petiolule: The stalk of a leaflet, corre-
sponding to the petiole of a leat.
Phanerogam: A flowering, seed-produc-
ing plant; a seed plant (spermato-
phyte) as distinguished from a
eryptogam. The higher of the two
main divisions, or subkingdoms, into
which the vegetable kingdom is di-
vided ; in turn separated into angio-

sperms and gymnosperms.

Phloem: Soft bast or sieve tissue in
plants. The outer of the two com-
ponent parts of fibrovascular bun-
dles. Phloem consists of Sieve tubes
with the accompanying cells and
parenchyma,

Photosynthesis: The complex process
by which starch (CsH»O;s) is manu-
factured by the chloroplasts, or

A B

FIGURE 54.—Pistil-
late (female) floral
parts of a sedge
(Caren festivella) :
A, Perigynium; B,
seale, which sub-
tends A

GLOSSARY OF BOTANICAL TERMS 7

chlorophyll-bearing cell granules, in
the presence of light (normally sun-
light) and usually in the leaf. The
starch is gradually derived from
water and carbon dioxide. The
water (H:O) is obtained from the
soil by means of the root hairs on
the roots, and carbon dioxide (CO:)
is abSofbed from the air through the
stomata. In the process of photo-
synthesis free oxygen (QO) is given
off through the stomata, and this is
the scientific basis for the popular
dictum that plants purify the air.

Phototropism: The common phenome-
non exhibited by plants or their or-
gans in growing toward or turning
to a source of light. Heliotropism
(turning toward the sun) is prac-
tically Synonymous with phototrop-
ism, though similar tropisms can be
induced by artificial light.

Phyllary: One of the (often sepallike)
involucral bracts subtending the
flower head of a composite.

Phyllo- (or -phyll): An element
(Greek) in compound words Ssignify-
ing leaf.

Phylogeny: The life history, evolution,
or genetic relationship of a group
(as an order, family, genus, species,
or race) of plants or animals, as dis-
tinguished from ontogeny, which
concerns the study of an individual
plant or animal.

Physiology: The branch of biology
which deals with life processes and
functions. Plant physiology is the
study of how plants grow and repro-
duce and of the varied functions of
their organs or other parts.

Pilose: Hairy with soft slender hairs.

B

Ficgurp 55.—Pinnate leaves: A, Odd-
pinnate leaf of vetch (Vicia), with
the terminal leaflet represented by a
tendril; B, even-pinnate leaf, ag in
Cassia

Pinna (pl. -ae): A main or primary
division of a pinnate leaf, a single
leaflet if the leaf be simply or once
pinnate. Each of the leaflets shown
in Figure 55 is a pinna; each of the

main divisions in the bipinnate leaf
shown in Figure 12 is a pinna; its
individual leaflets are pinnules.

Pinnate: Having the parts (usually
said of leaves) arranged on each side
of a common axis; a compound leaf
with opposite leaflets (fig. 55, A, B),
as in ashes or peavines, is pinnate.

Pinnatifid: Pinnately or oppositely
(featherwise) cleft or parted almost
to the midrib, or else lobed to the
middle. (Figs. 138, 18, 40 B, and
50.) Approaching pinnate.

Pinnule: An ultimate leaf division, or
leaflet, of a bipinnate leaf (fig. 12) ;
the main division of a pinna. Ina
thrice pinnate leaf the pinne would
be divided into pinnules and each of
the pinnules, in turn, would be pin-
nately divided into leaflets.

Pistil: The female or seed-producing
organ of a flower, consisting typi-
eally of ovary,
style, and stig-
ma (fig. 56),
the style, how-
ever sometimes
wanting.

Pistillate: Fe-
male; bearing
pistils or seed-
producing or-
gans only. Said
of flowers

FIGURE 56.—A _ pis-
til: a, Stigma; 3d,

which are pro- style; c, ovary; d,

vided with pis Pye vertinal come
tils but not of ovules (rudi-
with stamens, mentary seeds)
and of individ-
ual inflorescences and plants having
only pistillate flowers. Expressed
by the symbol @2 (Venus’s-looking-
glass).

Placenta (pl. -@): That portion of
the ovary on which the ovules are
borne (fig. 56, @) ; placente of sim-
ple pistils are marginal and, com-
pound pistils, usually axile, parietal,
or basal.

Plumose: Feathery or featherlike; hav-
ing fine hairs on each side, like the
plume of a feather. (Fig. 57, @.)

Plumule: The little, often featherlike
bud, at the summit of the radicle in
an embryo or germinating seedling,
situated between the two cotyledons
in a dicotyledonous plant, and from
which the mature plant stem and
leaves eventually develop.

Pollen: The fertilizing floral dust or
powder; fecundating granules de-
veloped within the anther.

Poly-: A Greek prefiix meaning many.

Polycotyledon: A seedling with numer-
ous (at least three) cotyledonous
leaves, or a plant whose seedlings

28

are of that sort.
are polycotyledons.

Polygamous: Having both perfect and
unisexual, or imperfect (i. e., either
staminate or pistillate) flowers
borne on the same individual as, for
example, in certain species of maple.

Polypetalous: Having the petals dis-
tinct (choripetalous), and especially
if numerous; the opposite of gamo-
petalous.

Polysepalous: Having the sepals dis-
tinct (chorisepalous), and especially
if numerous; the opposite of gamo-
sepalous.

Pome: The fleshy, applelike fruit of a
member of the apple family (Mala-
ces); an apple; also, though less
exactly, a rose hip or haw or other
smaller fruit of somewhat similar
character of the rose family,

Thus, most pines

Plumose
pappus bristles at apex

FIGURH 57.—a,

of 6, the beaked fruit
(achene) of salsify, or
vegetable-oyster (Trcego-
pogon porrifolius)

Prickle: A sharp, pointed emergence
from the bark and readily pulling
off with it, as a rose prickle. Spines
or thorns partake of the nature of
branches or twigs and are more
deeply seated than prickles.

Process: A projection or emergence,
usually small, from the edge or sur-
face, as the spiny processes on the
leaf margins of agaves.

Procumbent: Lying on the surface of
the ground, even from the first, said
especially of stems. Same as pros-
trate.

Proliferation: The production of new
parts rapidly and repeatedly from
buds, offsets, etc.; rapid succession
of cell division or a new growth so
formed.

Proliferous: Reproducing freely by
vegetative means, as, for example,
offsets or buds; developing leafy
shoots from a flower or flower head,
ete.

Prosenchyma: Vascular tissue com-
posed of elongated, mostly thick-

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

walled, fibrous, pointed cells, with-
out intercellular spaces; one of the
two general types of tissue in the
higher plants, the other being the
parenchyma.

Prostrate: Lying on the surface of the
ground, even from the first; said
especially of stems. Same as pro-
cumbent.

Prothallium (pl. -ia): The same as
prothallus.

Prothallus: The sexual stage or gener-
ation (gametophyte) of ferns and
related cryptogams; it consists of a
small, usually flat and green body
(thallus) attached to the ground or
other growing surface by rootlets
(rhizoids) on the under surface, and
bears the male and female organs
(antheridia and archegonia) either
on the Same or on separate plants.
See alternation of generations.

Protoplasm: The colorless, semifiuid,
highly complex, nitrogenous (pro-
teid) material found in all living
tissue, both plant and animal, and
which is the physical basis of life.

Pruinose: Beset, as if dusted, with a
white, frostlike bloom, or indument,
of fine vegetable wax, as, for exam-
ple, on the stems and leaves of cer-
tain crucifers, on certain berries and
other fruits, ete. Glaucous to an
extreme degree. (Latin pruina,
hoarfrost. ) |

Pseudo-: A prefix (Greek) signifying
false.

Pteridophyte: A fern or fern ally. A
member of the natural group (phy-
lum) Pteridophyta, consisting of the
various orders and families of ferns,
horsetails, clubmosses, quillworts,
and other of the higher nonflowering
plants, or cryptogams; the vascular
eryptogam of the older botanists.
Save for the tree ferns of the Trop-
ics all living pteridophytes are
herbs.

Puberulent: Very finely pubescent.

Pubeseent: In current botanical usage
a general term meaning hairy; spe-
cifically, however, the term means
downy haired; covered with fine,
soft short hairs (pubescence).

Pulvinate: Resembling a cushion.

Pulvinus: A cushionlike appendage, as
the hairy pulvini in the axils of the
inflorescence branches of beard-
cushion witchgrass (Panicum bar-
bipulvinatum).

Punctate: Dotted, especially if beset
with minute holes or depressions,
as the small translucent glands in
the leaves of St. Johnswort (Hyper-
icum). Sometimes used as a syno-
nym of minutely papillate, i. e., be-

GLOSSARY OF BOTANICAL TERMS

set with minute dotlike projecting
appendages.

Pungent: Tipped with a hard, rigid,
prickly point, as a pine needle.

Pustulate: Beset with pimplelike or
blisterlike, elevated and sharply de-
fined areas (pustules).

Pustule: A pimplelike or blisterlike
area, raised above the surrounding
surface and sharply circumscribed.
A pustule may be pathological as
the pustules (blisters or cankers)
on the stem of a white pine infested
with blister rust, or may be normal
and morphological as the pustulate
glands at the base of a peach or
plum leaf.

Putamen (pl. -mina): The hard stone
or pit (endocarp) of a drupe. The
pits of cherries, peaches, plums, and
the like are putamina and, anatomi-
eally, are inner layers of the coat
(pericarp) of the fruit rather than
belonging to the seed itself.

Pyriform: Pear shaped.

Pyxidium: Same as pyxis.

Pyxis: A capsule or pod which opens
horizontally (circumscissile dehis-
cence), the top of the pod falling
off as a lid to permit seed dissemi-
nation. (Fig. 58.) A diminutive
pyx (box or casket of a convention-
al shape). The fruits of the Brazil
nut, henbane, plan-
tain, and portulacas,
for example, are
pyxes.

Q. v.: To which refer
(Latin, quid vide),
an abbreviation used
in cross references.

Quadrat: A _ rectangu-
lar, usually square
sample plot used in
ecological and other
biological studies ; es-
pecially such a plot
containing 1 square
meter. (A larger sample plot is
often termed a major quadrat.)

Quinquefoliolate: Having five leaflets
(Latin, quinque, five + foliolum,
leaflet), as the leaves of cinquefoils
(Potentiila spp.).

Race: A breed or strain, especially if
of a domesticated species and pro-
duced by artificial selection; a taxo-
nomic group lower and less constant
than a species, aS a white-flowered
race of a normally blue-flowered
larkspur species. Partly synony-
mous with subspecies and variety
but typically of lesser importance.

Raceme: A simple, elongated, indeter-
minate flower cluster, the rachis
bearing a series of 1-flowered pedi-

. FIGURE 58.—A
pyxis

29

cels, the lower flowers blossoming
earlier than the upper flowers (cen-
tripetal). (Fig. 59.)

Racemose: Having the characteristics
of a raceme; racemelike; raceme
bearing.

Rachilla: The axis of
a spikelet, the pro-
longation of the
pedicel.

Rachis: The axis of a
spike, raceme, or
branch of a panicle.

Radicle: The rudimen-
tary stem of the
plant embryo ina
seed; the basal tip
of the lower, free
portion turns down-
ward into the earth
(exhibits geotro
pism) and becomes
the root of the seed-
ling plant, while the
upper extremity ex-
hibits heliotropism,
pushing the cotyle-
dons into the light.

Raphe (pronounced
ray’-fee; Greek,
rhaphe, a seam): A

FIGURE 59.—A
raceme, as in

: . pyrola, or.
seamlike rid ge or shinleaf (Py-
furrow (as on the rola)

human tongue), es-

pecially (1) the ridge connecting
the hilum and chalaza of an ana-
tropous or amphitropous ovule,
marking the fusion of the stalk
(adnate funicle) and body of the
inverted ovule, adjoining the point
of attachment on the placenta, and
(2) a prominent medial line or
suture, often showing the union of
two symmetrical halves of an organ
or part, as on the pod of a pea or
loco, a sporocarp of pepperwort
(Marsilea), a diatom valve, or a
seed of pitcherplant (Sarracenia).
Often spelled rhaphe.

Ray: In composites (as in daisies) one
of the marginal, usually colored and
petallike flowers which are called
“ligules” by some authors. In
umbellifers, a branch of an umbel.
(Fig. 74, c.)

Receptacle: The axis or support of a
flower or flower head ; the somewhat
enlarged end of the flower stalk
upon which numerous flowers or the
organs of a flower are borne. Often
called torus.

Reflexed: Bent abruptly backward.

Reniform: Kidney shaped.

Repand: Gently wavy or fluted mar-
gined. Same as undulate. Uneven,

30

slightly sinuous leaf margins which
bend moderately inward and outward
in succession are repand. (Fig. 60,

Ficurr 60.—Two types of leaf _mar-

gin: A, serrate; B, repand, or
undulate
B.) Repand, however, is not so

deeply wavy as is sinuate.

Resin-duct: A canal, tube, or vessel in
which resin is secreted. Resin ducts
are exemplified in the leaves, wood,
and bark of conifers.

Resiniferous: Bearing’ or
resin.

Respiration: Literally, breathing. In
plants, the taking in of free oxygen
from the air and the giving off of
carbon dioxide (CO:z) (both in rela-
tively much smaller quantities than
in animals), with some rise in tem-
perature as a result of oxidation
(combustion) ; the diffusion and in-
terchange of gases between the at-
mosphere and _ the _ intercellular
spaces of plants, especially in the
leaves. In photosynthesis (a reverse
process) plants utilize so much car-
bon dioxide (CO:) and give off so
much oxygen that they may be said
to purify the air. The hotbed of
gardeners takes advantage of the ac-
tive respiration of certain bacteria
to produce higher growing tempera-
tures.

Reticulate(d): Net veined,
veins like a network.

Retrorse: Directed back or downward;
as retrorse hairs or spines.

Retuse: With a rounded summit very
shallowly notched at apex. (Fig.
61, A.)

Revolute: Rolled backward (as a leaf)
from the margin or apex upon the
lower surface. The opposite of in-
volute.

Rhaphe: Same as raphe.

Rhizome: A rootstock. In its simplest
form, merely a creeping, usually
thickened stem or branch growing
partly or entirely beneath the sur-

yielding

the leaf

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

face of the ground. That a rhizome
is really a stem and not a root is
evident from its manner of growth,
from its consisting of a succession
of joints, and from the scales which,
as true though degenerated leaves,
are borne at these joints and which
often have buds in their axils.
Rhombic: Literally, having the form
of a rhombus, an equilateral paral-
lelogram differing from a square in

having the angles oblique —— ~~
instead of square; but used broadly
as diamond shaped, or lozenge
shaped.

Rhomboid(al): Literally, having the
form of a rhomboid, but used broadly
for an elongated figure roughly quad-
rilateral, having the opposite sides
equal, the angles oblique, and the

adjacent sides unequal. ey 5

Rootstock: A rootlike stem or branch
under or sometimes on the ground;
a rhizome.

Rosette: A dense basal cluster of
leaves, as in the common dandelion,
eaused by dwarfing of the true
(leafy) stem, and so named because
of its resemblance to the petals of
a double rose. Rosettes are common,
for example, among winter annuals
and alpine herbs.

Rostrate: Beaked, as the rostrate keel
of crazy weed or Lambert loco (Oxy-
tropis lambertii).

Rotate: Wheel

shaped; having
the parts hori-
zontally flaring.

A term often
used for gamo-
petalous corollas
having a much re-
duced tube and a
widespread limb.
For example, cer-
tain genera in the
Gentian family
(e. g., Frasera,
Sabbatia, and
Swertia) are largely distinguished
by their rotate corollas.

Rugose: With wrinkled or creased sur-
face; roughened by wrinkles.

Ficurn 61.—Two
degrees of ter-
minal notching,
as in leaves,
petals, ete.: A,
Retuse; B,
emarginate

Rugulose: Minutely rugose; slightly
wrinkled.
Runcinate: Coarsely and _ pinnately

lobed with the pointed lobe tips
curved toward the base of the leaf,
as in the common dandelion. (Fig.
62.)

Runner: A long, slender, tendrillike
leafless form of creeping branch,
prostrate on the ground. Each run-

GLOSSARY OF BOTANICAL TERMS 31

ner, after having grown to its full
length, strikes root from the tip (it
sometimes roots at the joints also,
in which case it may merge into a
stolon), fixing the tip to the ground,
then forms a bud at that point,
which later develops into a tuft of
leaves and so gives rise to a new
plant.

FicurRE 62.—Runcinate leaf, as
in the common _ dandelion
(Leontodon taraxacum)

Sac: A soft, membranous, pouchlike
appendage or part, usually closed ex-
cept for a relatively narrow opening,
as an anther, or pollen sac.

Sagittate: Shaped like an arrowhead,
with the acutish basal lobes directed
downward. (Fig. 638.)

FicguRE 63.—Sa git-
tate leaf, as in but-
terbur, or false
coltsfoot (Petasites
sagittata)

Salverform: A term used to describe a
type of gamopetalous corolla with a
slender tube and wide, flaring limb,
as in a phlox flower.

Samara: A dry-winged indehiscent
fruit, as the fruit of maples, ashes,
ailanthus, hoptree, ete.

Sarcocarp: A fleshy mesocarp, or mid-
covering of a fruit,.as in a peach or
plum ; also, though more loosely, the
fleshy portion of any fleshy fruit.

Saprophyte: A plant which lives on
decaying organic matter, such as
pinesap (Hypopitys) and Indianpipe
(Monotropa), mushrooms, and many
other fungi. Such plants are desti-
tute of green coloring matter (chlor-
ophyll).

-Scabrous: Rough or harsh to the touch.

Scale: In botany a plant organ or part
more or less reminiscent of the scale
of a fish or reptile; specifically: (1)
One of the partially overlapping
(imbricated) parts of a bulb, as of
a lily bulb; (2) a modified leaf
forming part of the protective cov-
ering of a leaf bud or flower bud;
(8) the bract subtending the peri-
gynium in the sedge genus Carex
(fig. 54, B); (4) a bract of a cone
or catkin; and (5) a rudimentary
leaf on a rhizome. There is prob-
ably a growing tendency in botany
to confine, so far as possible, the use
of scale to the basal and under-
ground portions of the plant and to
use bract for analogous parts in the
inflorescence.

Scape: A leafless peduncle, or main
flower stalk, arising from the under-
ground parts of a plant; the pedun-
cle of an acaulescent or apparently
stemless plant. The stalk of common
dandelion is a scape.

Scapose: Bearing a scape (or scapes),
or resembling one.

Scarious: Thin, membranous, dry, and
not green.

Schizocarp: Literally, splitting fruit.
A dry compound fruit, as in the
mallow family, splitting up at ma-
turity into several indehiscent 1-
seeded carpels
(mericarps) ; the pe-
culiar dry twin-fruit
of the umbellifer, or
parsnip, family
(cremocarp) iS a
form of schizocarp.
(Fig. 64.)

Sclerenchyma: Hard,
thick-walled cell tis-
sue, as in nut shells,
the grit cells of
pears, ete.

Scorpioid: Coiled at the tip, like the
tail of a scorpion (said especially of
inflorescences). (Fig. 65.) Partly
syhonymous with circinate.

Section: A natural division of a taxo-
nomic group, especially of a genus
and, hence, usually more or less

Ficurp 64.—A
schizocarp,
as in round-
leaf mallow,
or ‘“‘cheeses’’
(Malva_ ro-
tundifolia)

32

synonymous with subgenus. In very
large genera the section is often a
division of the subgenus. e
Secund: Borne on one side of an axis;
1-sided, as the inflorescence of blue

grama. The
same as mono-
stichous.

Seed: A fertilized
and matured
ovule; the em-
bryo (product
of sexual con-
jugation) of a
flowering plant
with all its at-

tendant, and
matured, enve-
lopes.

FIGURE 65. — Scor-
pioid inflores-

Semi-: A _ prefix
(Latin) mean-
ing half.

Sepal: One of the
separate parts (modified leaves) of
the outer and lower series of the
floral envelope (perianth) ; a divi-
sion of the calyx corresponding to a
petal in the corolla. (Fig. 66, A, 0b.)
Also, though less precisely, one of
the more or less fused divisions of
a gamosepalous calyx (as the five
united sepals of phlox).

Septate: Provided with one or more
partitions (septa), as the septate
pods of tickclover, or ‘‘ beggar-ticks ”
(Meibomia spp.).

Septum (pl. -ta): A partition, as, for
example, between the seeds in a pod
of the legume (pea) family.

cence, as in the
genus Phacelia

FieurrE 66.—A, Floral enve-
lopes: a, Petals; 6, sepals;
B, top of pistil; a, stigma;
b, style

Sericeous: Silky; closely covered with
fine appressed soft straight hairs of
silky texture.

Serrate: Saw-toothed; having sharp,
forward or upward pointed teeth
(serrations, or serratures). (Fig.
60, A.)

Serration, or serrature: A saw-tooth-
like projection, or tooth, as on the
margin of a leaf; a state or condi-
tion of being toothed like a saw,

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

Serrulate: Finely or minutely serrate.

Sessile: Literally sitting, i. e., without
a stem or stalk; a sessile leaf is
without a petiole, or leafstalk, sit-
ting directly on the axis or stem of
the plant. For example, the sessile
leaves of St. Johnswort; the sessile
cones of hemlock; the sessile an-
thers of mistletoe. In a spike all
the flowers are sessile.

Seta (pl. -ae): A bristle, or stiff thick
hair.

Setaceous: Bristlelike.

Setose: Bristly; beset with setae, or
bristles.

Sheath: That portion of a leaf (as in
grasses, sedges, and rushes) which
envelops the stem (fig. 67, c), the
terminal free portion of the leaf
being known as the lamina, or blade.
A modified petiole.

Ficurp 67.—Three parts of a grass;
a, Culm; 0b, blade (or lamina) ;
oc, sheath

Shrub: A woody (fruticose or frutes-
cent), perennial plant, differing
from a perennial herb by its persist-
ent and woody stems, and from a
tree by its low stature and habit
of branching from the base. There
is, of course, no hard-and-fast line
between herbs and shrubs or be-
tween shrubs and trees; all possible
intergradations occur. Under very
favorable growth conditions, species
of shrubs frequently become trees
(arborescent) and vice versa. Also
there are a few cases of plants
(such as the castor-bean plant,
Ricinus) which are herbaceous in
temperate climates but shrubby or
even arborescent in tropical or sub-
tropical regions.

Sieve tube: A canal or tubular vessel
composed of thin-walled cells placed
end to end in rows and separated,
usually terminally but sometimes
laterally, by thin perforated parti-
tions called sieve plates, Sieve

GLOSSARY OF BOTANICAL TERMS

tubes with their companion cells
compose the soft bast (sieve tissue)
or phloem of the outer fibrovascular
bundles of the higher plants. The
sievelike partitions permit the
strands of protoplasm, or living tis-
sue, to extend through the tubes and
facilitate the transportation of the
products of assimilation, of which
transfer the sieve tubes are the chief
agency.

Silicle: A small silique, especially one
that is as broad as or broader than
long; as the silicles of pepperwort
and shepherd’s-purse.

Silique: The peculiar, mostly elcngat-
ed, 2-valved capsule or pod of the
mustard family (Brassicacesr, or
Crucifere).

Simple: Unbranched or undivided;
said, for example, of stems, ieaves,
and inflorescence; the opposite of
compound. <A simple pistil is one
carpel, representing morphologically
a single folded leaf.

Sinistrorse: Spirally twisting to the
left. Said of vines that twine in a
clockwise direction, as bindweed and
morning-glory.

Sinuate: Strongly wavy margined;
more deeply wavy than undulate, or
repand.

Sinus: The depression between two ad-
joining lobes (literally gulf or
bosom).

Sorus (pl. -ri): A fruiting dot on the
fertile frond of a fern; an assem-
blage of sporangia.

Sp.: Species (singular) ; pl. spp.

Sp. nov.: New species (Latin, species
nova).

Sp. Pl.: Species Plantarum (an impor-
tant work of Linneus, the first edi-
tion of which, published in 1753, is
regarded by both the International
and American Codes as the starting
point of binomial plant nomencla-
ture).

Spadix: A floral or fruiting spike with
a thickened fleshy axis, usually
densely flowered, the flowers often
more or less imperfect, and charac-
teristically subtended by a spathe.
This type of inflorescence is charac-
teristic, for example, of the arum
family (including callas, jack-in-the-
pulpits, skunkeabbage, and sweetflag
or calamus).

Spathe: An enlarged, membranous,
Sheathing bract or bracts subtending
an inflorescence, and especially the
characteristic bract (often colored)
associated with a spadix as the
spathe of a jack-in-the-pulpit or
calla lily.

er Essa Fe

3d

Spatulate: Shaped like a spatula; i. e.,
broad and rounded at apex and with
a narrowed, relatively short base.
(Fig. 38, D.)

Species (pl. species): A group of indi-
viduals with so many characteristics
in common as to indicate a very high
degree of relationship and a common
descent. ‘The unit of plant and ani-
mal classification. White pine (Pinus
Strobus), aspen (Populus tremu-
loides), Colorado columbine (Aqui-
legia cerulea), and the domestic
horse (Hquus caballus) and sheep
(Ovis aries) are familiar illustra-
tions of species. Genera are com-
posed of species, which in turn often
comprise various subspecies and va-
rieties,

Specific: Of or pertaining to a species,
as a Specific character or specific
name.

Spermatophyte: A _ seed-producing
plant; a phanerogam.

Spiciform: Having a spikelike form,
as the spiciform panicle of timothy.

Spicule: A very small, needlelike yet
more or less fleshy body, appendage,
or point as, for example, the spicules
of cacti.

Spike: An elongated flower cluster in
which the flowers are sessile, i. e.,
without indi-

vidual flower 3
stalks (pedi- <b
cels). Wheat, C Bee
spearmint, and e
mullein are fa- rads

miliar examples +

of plants whose & h

flowers are

borne in spikes. A
Spikelet: A name

applied to each

of the main

components of a

grass or sedge

inflores

FIGURE 68.—A, Spike-
let of Kentucky

cence. (Fig. blue grass (Poa
68.) A grass Dratonatay a—f

spikelet usually lemmas (with their
consists of two
glumes and one
or more florets;
it may be erect
or pendulous,
sessile, or pedi-
cellate. Grasses are distinguished
primarily by differences of spikelet
construction.

Spine: A sharp-pointed, rigid, deep-
seated emergence from a_ plant.
Spines differ from prickles in not
pulling off with the bark (epidermis)
of the plant; they differ from thorns
by absence of vascular tissue.

florets) ;

lemma of same
showing arachnoid
(cobwebby) hairs
at base

34

Spinescent: Becoming spiny; tapering
to a rigid, Sharp point. Said espe
cially of the sharp-pointed tips of
branches such as are characteristic,
for example, of numerous southwest-
ern shrubs.

Spinose: Beset with spines or thorns,
as the spinose branches of barberry.

Spinule: A small or minute spine.

Spinulose: Minutely spiny; béset with
Spinules.

Sporange: Same as sporangium.

Sporangium (pl. -ia): The minute,
usually globular case in which the
spores of seedless plants (crypto-
gams) are produced and somewhat
analogous to the ovary of a flower-
ing (seed) plant.

Spore: The 1-celled, powderlike fruit-
ing body (somewhat analogous to a
seed in a seed plant) of a crypto-
gam, produced asexually, ana with-
out an embryo.

Sporophore: That part or organ of a
sporophyte which produces’ the
spores.

Sporophyte: A spore plant; a spore-
producing plant; the asexual plant
developed sexually from the gameto-
phyte of a cryptogam. The sexless
plants ordinarily recognized as
ferns are sporophytes which grow
from fertilized eggs (odspores) pro-
duced in the preceding Sexual gen-
eration. See alternation of genera-
tions,

Spur: A hollow, saclike, or tubular ex-
tension of a floral organ, as in G€o-
lumbine, larkspur, or violet flowers.

Squama (pl. -@): A plant organ or
part resembling a scale of a fish.
Same as scale.

Squamate: Same as squamous.

Squamella (pl. -e): A chaffy bract
or scalelike appendage in the pap-
pus of a composite; a small scale.

Squamellate: Same as squamulose.

Squamose, or squamous: Scaly; pro-
vided with squame.

Squamule: A small scale. Sometimes
used as a synonym of lodicule.

Squamulose: Provided with squamel-
le, or small bracts or scales; mi-
nutely squamous.

Squarrose: Having the parts or ap:
pendages widespreading. As the
squarrose scale prickles of a digger
pine cone, or the squarrose involu-
eral bracts (phyllaries) of the
Macheranthera subgenus of the
genus Aster.

Stamen: A male floral organ which
bears pollen grains; it usually con-
sists of a filament, or stalk, and an
anther, or pollen sac. (Fig. 69.)

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

Staminate: Male; bearing stamens, or
pollen-producing organs, only. Ex-
pressed by the symbol ¢ (Mars’
dart).

Standard: The uppermost petal of a
papilionaceous flower (i. e., of a pea
family fiower).

(Fig. 48, a.)

Often called the

banner, or vex- a
illum. -

Stellate: Starlike
or starshaped,
the slender seg-
ments or divi- b
sions radiating
from a common
center; as, for
example, the
stellate hairs of
certain species of globemallow (Sphe-
ralcea) and whitlowwort (Draba).

Sterile: Barren; said of shoots that
produce leaves but no flowers; of
anthers (pollen sacs) that are rudi-
mentary and do not function, etc.;
also synonymous with imperfect.

Stigma: The part (usually the tip and
mostly sticky or hairy) of a pistil
through which fertilization by the
pollen grain is accomplished. (Fig.
66, B, a.)

Stipe: A stalklike support of an organ
or part, as the leafstalk of a fern;
a slender stalklike narrowing as of
the base of an ovary ora pod. (Fig.
70, 0.)

FicurH 69.—A_sta-
men: a, Anther;
bo, filament

FicurE 70.—Stipitate capsule or
pod of Rocky Mountain bee-
weed (Cleome serrulaia): a,
Pedicel; 0b, stipe; c, body of
capsule

Stipitate: Provided with a stipe, or
slender and stalklike base. (Fig.
70.)

Stipulate: Provided with stipules.

Stipule: One of a pair of appendages
borne at the base of certain petioles,
or leafstalks; often the stipules are
more or less united. (Fig. 71.)

Stolon: A trailing or reclining branch,
above ground, which strikes root

GLOSSARY OF BOTANICAL TERMS

where is touches the soil, there send-
ing up new shoots which, later, be-
come separate plants. Many plants
multiply vegetatively in this way.
Stoloniferous: Bearing stolons.

Fieurn 71.— Stipules:
A, A pair of stipules
united for most of
their length and ad-
nate to the base of
the petiole; 6, con-
nate-perfoliate stip-
ules

Stoma (pl. -ata): One of the small
openings (breathing pores) on the
surface of a leaf, especially on the
under side, whereby contact is estab-
lished with the atmosphere, and
essential in such vital processes as
respiration, photosynthesis, and
transpiration.

Stomate: The same as stoma.

Striate: Marked with slender longi-
tudinal grooves or furrows; minutely
channel streaked.

Strict: Narrow and erect; said, for
example, of panicles, the branches
of which are erect and closely ap-
pressed to the main axis of the in-
florescence, giving a spikelike ap-
pearance.

Strigose: Beset with appressed, rigid
hairs.

Strobile: The (often conical) dry mul-
tiple fruit of pines, spruces, firs,
hemlocks, and other conifers, con-
sisting of numerous partially over-
lapping (imbricated) scales arranged
symmetrically around a_= central
axis and bearing naked seeds on
their upper surface. Same as cone.

Style: The stalklike and often slender
portion of the pistil connecting the
stigma with the ovary. (Fig. 66,
B05)

Sub-: A prefix signifying nearly or
below.

Subacute: Acutish; somewhat acute.

Subcordate: Shallowly heart shaped;
shallowly 2-lobed at the base.

Subcoriaceous: Somewhat leathery in
texture.

Subgenus: A division of a genus; a
group of closely related species

30

within a genus. Raspberries and
blackberries, by way of illustration,
are subgenera of the genus Rubus;
cherries (Cerasus) and chokecher-
ries (Padus) are subgenera of the
plum genus (Prunus). Subgenera
furnish occasion for a large num-
ber of plant synonyms since many
botanists will prefer to raise them
to generic rank and, of course, there
will never be complete unanimity of
opinion as to what are genera and
what are subgenera. Subgenera, es-
pecially of very large genera, are
sometimes divided into’ sections.

Subspecies: A taxonomic rank imme-
diately below a species; by some
authors regarded as a synonym of
variety, but if subspecies and va-
rieties are both recognized, then va-
riety ranks below subspecies.

Subtended: Literally, held (from) un-
derneath; included in an axil. In-
closed or embraced. As the florets
of a grass spikelet subtended by
glumes, or the umbel of an umbel-
lifer subtended by an involucre.

Subulate: Awl shaped.

Subcylindric: Almost cylindrical but
tapering somewhat; terete.

Succession: A progressive change in
the vegetation of an area or region;
complete and continuous invasion re-
sulting in radical changes from the
original ground cover. For exaim-
ple, a forested area is denuded of its
timber by fire and a succession of
shrub or weed species may replace,
at least temporarily, the forest.

Succulent: Juicy, watery, or pulpy; as
the succulent stems of cacti or the
succulent fruits of the apple family
(Malacee).

Sucker: A branch or shoot from a
creeping underground stem which
ascends above ground and tends
eventually to become a separate in-
dividual plant. Suckers are common
in many woody plants, such as
aspen, blackberry, elder, poplar, rose,
sassafras, and willow.

Suffrutescent: Literally, becoming un-
dershrubby. A term applied to per-
ennial plants which do not die down
quite to the ground each year, but
the stem bases, above the ground,
tend to be at least a little woody
and perennial. Marking the first
stage in the transition zone between
true herbs and true shrubs, and fol-
lowed by the suffruticose.

Suffruticose: Literally, undershrubby.
Applied to low perennials the lower
parts of whose stems are truly
woody and perennial, but the upper
parts herbaceous. Marking approxi-

36

mately the second stage in the tran-
sition from herbs to shrubs, of
which the first is suffrutescence.

Suleate: Grooved, especially if the
groove (sulcus) or furrow is deep
and longitudinal, as the sulcate
stone in the fruit of flowering dog-
wood or the suleate pod of sheep
loco (Astragalus nothorys).

Super-: A prefix (Latin) signifying
above, beyond, surpassing, and the
like. For example, superlabial
means above a lip, and superfoliar
refers to a region or object above
the foliage,

Superior: Lying above another organ
or part; said especially of an ovary
when the calyx and stamens are
free from it and attached below it.
Epigynous stamens are sometimes
ealled superior, because growing
from (adnate to) the top of the
ovary.

Supra-: A prefix (Latin) signifying
over, ° above, or beyond, where
growth or action is implied. For
example, “ supracrescent’ signifies
“crowing over” another part or or-
gan.

Suture: A seam, raphe, or seamlike
ridged or furrowed medial line; a
line of splitting or dehiscence. The
sutures of a pod are the lines where
the valves of the pod separate to
discharge the seeds.

Symbiosis: The living together of dis-
similar organisms; especially (as
opposed to parasitism) when the re
lationship is mutually beneficial.
As, for example, the alga and fungus
which compose a lichen; the nitro-
gen-fixing bacteria on the roots of
an aifalfa or clover plant; or the
yucca moths (Pronuba spp.) and
species of Yucca. ,

Symbiotic: Of or pertaining to sym-
biosis, as the symbiotic mycorrhizas
of an oak or orchid root.

Sympetalous: Having the petals more
or less united. The same as gamo-
petalous,

Syn.: Synoptic(al) ; synonym.

Synonym: A different botanical name
for the same plant; an untenable
specific or generic name. For ex-
ample, Abies menziesii is a Synonym
of Picea sitchensis (Sitka spruce),
Abies being wrong generically for
this tree and the specific name men-
ziesii later than sitchensis, which is
unpreoccupied and properly pub-
lished. There are two main divi-
sions of synonyms: (1) Typonyms,
or absolute synonyms, and which are
admittedly based on the same con-
cept or type; (2) those whose iden-

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

tity is a matter of individual taxo-
nomie opinion. To the latter cate
gory belong segregated genera and
species about whose integration with
other genera and species there can
never be universal uniformity of
opinion among botanists.

Systematic botany: See taxonomy.

Taxonomy: The science of classifica-
tion. In botany synonymous with
systematie botany, which is the clas-
sification or arrangement of plants
according to their natural relation-
ships and the principles underlying
such classification.

-taxy (or -tazis): A suffix (Greek)
signifying arrangement, as phyllo-
taxy, the arrangement of leaves on
a stem.

Tegule: One of the (often sepallike)
involucral bracts subtending the
flower head of a composite (a term
introduced by the late C. VY. Piper,
of the United States Department of
Agriculture). Same as phyllary.

Tendril: A slender, modified branch,
commonly spirally coiling at the tip,
and serving as an organ of support,
as in clematis, cucurbits, grapes, pea
vines, and vetches.

Terete: Elongated and round in cross
section; cylindrical, except that
terete may also be tapered.

Ternate: Arranged in threes.

Test.: By witness, statement, or au-
thority of (Latin, teste); same as
fide.

Tetra-: A prefix (Greek) signifying
four.

Tetradynamous: Having six stamens,
four of them longer than the other
two (literally, four having the pre-
dominance) ; a term introduced by
Linnezus. The flowers of crucifers
(members of the mustard family)
are tetradynamous.

Tetramerous: Having the parts in
fours.

Thallus: An often flattened, vegetative
organ or body of a plant not differ-
entiated into stem and leaf; the
main body of such plants as duck-
weeds, lichens, and liverworts.

Thorn: A hard, sharp-pointed plant
emergence, more deeply seated than
a prickle. A thorn is a more or
less yascular (thus differing from
spine), relatively short, modified
branch or twig, produced from a
bud. Familiar examples are seen in
the case of hawthorns (Crategus
spp.).

Thyrse, or Thyrsus: A more or less
compact or contracted, oblong to
ovoid-pyramidal, usually densely
flowered panicle, differing from a

GLOSSARY OF BOTANICAL TERMS

typical panicle in that, while the
main axis is indeterminate, the
branches (secondary and ultimate
axes) are determinate and cymose.
Certain species of Oreocarya and
Pentstemon, as well as cultivated
lilac, horsechestnut and grapes, fur-
nish familiar illustrations of a thyr-
soid inflorescence and fruit cluster.
The term is derived from _ the
thyrsus, or pinecone-tipped, Baccha-
nalian wanda of antiquity.

Tomentose: With a dense woollike
covering of closely entangled, matted
hairs (tomentum).

Tomentulose: Sparingly or minutely
tomentose.

Tomentum: Vegetable wool; densely
matted, woollike hairs.

Tooth: A toothlike projection, as a
tooth on the margin of a leaf.

Toothed: Provided with teeth, i. e,
toothlike projections, especially on
the margins; dentate; as a toothed
leaf or petal.

Torose: Knobby; knoblike; provided
with bulging prominences, more or
less rounded but with alternate
swellings and contractions (Latin,
torosus, having bulging muscles).
As ithe torose pods of catclaw
(Acacia greggit).

Torulose: Minutely torose; as in a
small pod constricted between the
seeds.

Torus: A flower receptacle, or axis or
support of a flower head; a Socket
or bed; a (usually round) swelling
or bulging; a knob or knot.

Toxic: Poisonous; induced by poison-
ing.

Toxicology: The science of poisons.
Plant or vegetable toxicology deals
with poisonous plants and their
toxic compounds (toxins).

Toxin(e): A poisonous organic com-
pound, proteid in nature, occurrent in
or from certain secretions of plants
and animals.

Tracheid: A more or less elongated,
often spindle-shaped woody (ligni-
fied) cell destitute of. protoplasm,
the cells occurring end to end in
rows, the series of cells serving as a
sort of continuous, water-conducting
vessel. One of the two important
mechanical elements in the struc-
ture of wood, of which the other is
bast. Tracheids are especially char-
acteristic and constitute the bulk of
the wood of conifers, and their walls
are marked by bordered pits or other
markings due to unequal thicken-
ing in the wall structure.

Transect: A cross section of vegeta-
tion, which may be a belt or merely

| =

37

a line, designed to show zonal dif-
ferences in the vegetation. In the
line transect the names of the in-
dividual plants are listed as they
are encountered along a measured
tape. In the belt transect, com-
monly delimited by two parallel
tapes at varying distances up to
a meter apart, the various species
encountered may be listed, tabu-
lated, or charted in their respective
places on the plotting paper.

Transpiration: The giving off into the
atmosphere by the plant, mainly
through its stomata and from the
under surfaces of the leaves, of
water in the form of vapor. This
water represents a surplus from
that taken in from the roots and
which is not required for photo-
synthesis. Xerophytes, or desert
plants, exhibit many modifications
to reduce transpiration to a mini-
mum.

Tree: An arborescent plant; a peren-
nial plant of considerable stature
with woody stems and a well-de-
fined, simple main stem (trunk or
bole).

Tri-: A prefix (Latin) signifying three.

Tribe: A group of related genera form-
ing a natural division of a family.
For example, the clover tribe (Tri-
foliew) of the bean family (Fab-
acer), Which tribe embraces the
true clovers (Trifolium spp.), sweet-
clovers or melilots (Melilotus spp.),
alfalfas, bur clovers, medics, lu-
cernes, and snail clovers (Medicago
spp.), ete. Tribe is in practice often

loosely used as a Synonym of sub-
family, but is actually a term of
lower rank and intermediate between
genus and subfamily.
Trifoliolate: Having three leaflets; the
leaves 3-divided, as in clover and
(Fig. 72.)

alfalfa.

Ficurp 72.—Trifoliolate leaf,
as in clover

Tropism: A turning or other reaction
of a plant or of its parts in response

38

to some external stimulus. For ex-
ample, geotropism (turning toward
the earth) is the tropism exhibited
by the root of a plant; phototropism
(or heliotropism) is the turning or
response of the aerial portion of the
plant to the source of light.
Truncate: Squared at the tip; termi-
nating abruptly as if cut off cross-
wise. (Fig. 73.)
Tube: A tubelike
part, especially
the united, tu-
bular basal por-
tion of a gamo-
petalous corol-
la, as distinct
from the limb
or free portion.
Tuber: A_ thick-
ened, usually
starchy (the

starch, how- yeuEE le Trun-

cate leaf, as in
ee apa yellow poplar, or
n some t tuliptree — (Lirio-
by inulin or dendron tulipifera)

other carbohy-

drates) swelling of a subterranean
stem serving for food storage and
vegetative reproduction. Potato,
sweetpotato, dahlia, Jerusalem-arti-
choke, and yam furnish familiar ex-
amples of tubers.
from buds known as eyes.

Tuberculate: Beset with small, pimple;
like prominences (tubercles) as, for
example, the tuberculate nutlets of
certain species of the genus Oreo-
carya in the borage family.

Tuberous: Of or pertaining to a tuber;
resembling a tuber,

Turbinate: Inversely conical;
shaped.

Turio (pl. -ones) ; Same as turion.

Turion (pl. -ns.): A scaly shoot (often
thick and fleshy succulent) produced
from a bud on an underground root-
stock ; familiar examples are seen in
asparagus, cinnamon-vine, and vari
ous mints.

Type: The specimen or specimens on
which a species (or a subspecies or
variety) is based and from which
the author of that species (or sub-
species or variety) described it. For
example, the type of Pentstemon
mensarum Pennell is A. F. McDuf-
fie’s plant specimen No. 151, United
States Forest Service range research
serial No. 7919, United States Na-
tional Herbarium (where deposited )
No. 1012411.

Type locality: The place where a type,
or type specimen, was collected.
Thus, the type locality of Pentste-
mon mensarum Pennell, above men-

top

Tubers sprout ]

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

tioned, is on the Grand Mesa (for-
merly Battlement) National Forest,
western Colorado.

Typical: Having the characteristics of,
or well matching the type of a
Species, variety, etc.

Typonym: An absolute synonym in
nomenclature, being a name based
on the same type, specimen, or con-
cept aS another and older name. See
synonym.

U. S. Nat). H(erb).: The United
States National Herbarium. The
herbarium in the Smithsonian Insti-
tution, Washington, D. C., one of the
largest herbaria in the world, where-
in are deposited the plant types be-
longing to the Federal Government.

Umbel: An indeterminate, convex or
flat-topped (umbrella-shaped) in-

florescence in which the rays or the
pedicels of the cluster arise from a
common point, the outer flowers
blooming earliest.

(Fig. 74.)

Ficurn 74.—Diagrammatic representa-
tion of a compound umbel (as in the
parsnip family): a, Bractlets consti-
tuting involucels; 6, pedicel (individ-
ual flower stalk); c, ray; d, bracts
constituting involucre; e, peduncle;
f, flower. The flowers at the top
are arranged in umbellets (secondary
umbels)

Umbellate: Borne in umbels; umbel-
like.

Umbellet: A small or secondary um-
bel; the division of a compound um-
bel. (Fig. 74, a, b, and f.) In pars-
nip (Pastinaca), for example, each
main umbel is divided into about 7
to 15 umbellets, each borne at the
apex of a ray.

Umbellifer: A member of the umbelli-
fer, or parsnip, family (Umbelli-
fere, Pastinacee, or Apiacesx).
Literally, umbel bearer.

Uncinate: Hook shaped; hooklike or
hooked. See barb.

Undulate: With gently wavy margins.
Same as repand. (Fig. 60, B.)

GLOSSARY OF BOTANICAL TERMS

Unguiculate: Clawed; conspicuously
narrowed at the base; as, for ex-
ample, the unguiculate petals of
catchfly (Silene).

Uni-: A prefix (Latin) signifying one.

Unifoliolate: A morphologically or
genetically compound leaf that is
reduced to one leaflet and thus ap-
parently is simple. Examples are
seen in barberry and viburnum.

Unisexual: One-sexed; having the
flowers or organs of one sex only—
either staminate (male) or pistil-
late (female). As the wunisexual
spikelets of buffalo grass, or the
unisexual inflorescence of holly.

Urceolate: Urn shaped; as the urceo-
late corolla of a manzanita or a
huckleberry.

Utricle: A small, bladderlike, indehi-
scent, 1-celled, usually 1-seeded fruit
with a thin, membranous covering

(pericarp), as the fruits of the
goosefoot family, Chenopodiacee.
(Fig. 75.) Also, the small bladders

of bladderwort (Utricularia) and of
various marine
alge. Sometimes
also used for the
perigynium of the
sedge genus, Ca-
rex. (From utri-
culus,a small
uterus, Or womb).

Utriculate: Provided
with a utricle.

V. i: See below
(Latin, vide in-
fra).

V. s.: See above
(Latin, vide su-
pra).

V.v.: I have seen (the plant) living
(Latin, vidi vivam) ; indicating that
the plant has been observed in a liy-
ing state and not merely as a dried
herbarium specimen.

Vaginate: Provided with or surround-
ed by a sheath (vagina), as the
vaginate culm of a grass.

Valvate: Opening by valves or provid-
ed with valves, as a fruiting cap-
sule; meeting together by the edges
without overlapping.

Valve: One of the parts or segments
into which a dehiscent pod or cap-
sule splits, as the two valves of a pea
pod.

Var. (pl. vars.) : Variety.

Varietal: Of or pertaining to a variety.

Variety: A division of a species. For
example, the white-flowered Aqui-
legia caerulea albifiora is a variety
of the typically blue-flowered Colo-
rado columbine (A. c@rulea). Vari-

FIGURE79.—Utri-
cle of fourwing
saltbush,
known in New
Mexico as
chamiza (Atri-
pler canescens)

39

eties are expressed either by trino-
mials (8-word names) or by the
species name, with authorities, fol-
lowed by the varietal name preceded
by var. and followed by the vari-
etal authority. Thus, the Latin
name for the common dwarf, moun-
tain, or Siberian juniper might be
written either as Juniperus commu-
nis sibirica (Burgsd.) Rydb. or as
Juniperus communis L. var. sibirica
(Burgsd.) Rydb. See subspecies.

Vascular: Containing vessels or ducts
for the transportation of fluids;
vascular tissue is tissue character-
jzed by the presence of such ducts.

Vein: One of the fibrovascular bundles
forming part of the framework
(skeleton) of a leaf; so called be-
cause of a fancied resemblance to a
human vein. Often a synonym of
nerve, but some authors prefer to
confine nerve to simple, more or less
parallel venations (as in a grass
blade).

Velutinous: Velvety in texture or to
the touch, as the velutinous-pubes-
cent culms and leaf sheaths of vel-
vet grass (Notholcus lanatus).

Venation: The arrangement or com-
plex of veins in a leaf.

Ventral: The opposite of dorsal; of or
pertaining to that side of a simple
pistil or other organ which faces the
axis, or center, of a flower; literally,
belonging to the stomach. As the
prominent ventral suture of the pod
of sheep loco (Astragalus nothorys).

Ventricose: Inflated or swollen on one
side; as the ventricose corolla
(flower) of certain pentstemons, or
the ventricose pod of certain loco
weeds and other legumes.

Vernation: The mode of arrangement
of a leaf and its parts in the bud,
before unfolding in the spring.

Verrucose: Beset with wartlike pro-
jections, as in the seedlike nutlets
of certain borages. More or less
synonymous with tuberculate.

Versatile: Attached near the middie,
with the ends more or less freely
turnable; said of anthers attached
by their middle to the filament, as
opposed to those attached by their
base (basifixed) or by their entire
length (adnate).

Verticil: An arrangement of three or
more leaves or other organs in a
circle about a stem or other common

axis. (Fig. 76.) The same as
whorl.

Verticillate: Arranged in a verticil, or
whorl. (Fig. 76.)

Vexillum: The topmost petal of a pa-
pilionaceous corolla (flower in the

40

pea tamily); same as banner and
standard.

Villous: Shaggy ; beset with long, soft,
weak hairs.

Virgate: Wandlike; rodlike; straight,
stiff, slender, and elongated. As,
for example, the virgate shoots of a
willow, or the virgate inflorescence
of gayfeather (Lacinaria sp.).

Viscid: Sticky or gummy to the touch;
glutinous.

Viscous: Same as viscid.

Weed: To the farmer, a plant out of
place, especially an aggressive and
pestiferous, often coarse, usually
herbaceous, introduced plant species
(such as crabgrass, dandelion, mus-
tard, plantain, and wild carrot)
which takes possession of cultivated
and fallow fields and pastures. To
the stockman, a weed is a herbace-
ous, nongrasslike plant occurring on
the range. A considerable number
of the weeds of the farmer are good
range forage plants of the western
stockman, especially on those ranges
where under unfavorable growing
conditions the same aggressiveness
which renders a species a pest in
agricultural land clothes it with
utility if it possesses palatability.
Some writers object to the use of
the term weed for nongrasslike her-
baceous range plants, but it is firmly
intrenched in western range par-
lance, and until a better term is
forthcoming and meets with favor,
it seems idle to attempt to replace
it. Clements has suggested the

term “forb.” Other suggestions are
“wort” and ‘“broad-leaved herb.”
Weeds, as applied to herbaceous

nongrasslike plants, constitute, with
browse, grasses, and_ grasslike
plants, the four main groups into
which western range plants are cus-
tomarily divided.

Whorl: An arrangement of three or
more leaves or other organs in a
circle about a stem or other com-
mon axis. (Fig. 76.) Same as ver-
ticil.

MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE

Whorled: Arranged in a whorl (fig.
76) ; same as verticillate.

Wing: A thin (or relatively so), wing- ~
like expansion or part, especially:
(1) One of the two lateral (side)
petals of a pea family blossom (pa-
pilionaceous corolla) (fig. 48, b),
and (2) a (usually lateral or angu-
lar) projection from a fruit, as in
many umbellifers, certain species of

saltbush (Atriplex), and of the
four-o’clock family (Allioniaces),
ete.

Winged: Provided with wings, as the
winged fruits of cow-parsnip (Her-
acleum lanatum).

FIGURE 76.—A whorl. Whorled
or verticillate leaves, as in
bedstraw (Galium) or lily
(Lilium)

Wort: An herb. An old Anglo-Saxon
word now seldom used except as a
suffix; e. g., figwort, St. Johnswort,
sandwort, whitlowwort, ete. <A pos-
sible substitute for the word weed
in the stockman’s sense. See weed.

Xerophyte: A plant adapted to arid
conditions; a desert plant. Cacti
are familiar examples of xerophytes.

Xerophytic: Of or pertaining to xero-
phytes or desert plants. AS a xero-
phytic habitat, or xerophytic leaf
and stem modifications.

Xylem: Woody tissue; one of the two
main divisions of fibrovascular
bundles (the other being phloem),
and consisting of wood fibers,
tracheal tissue, etc.

ADDITIONAL ITEMS

Acumen: A sharp, tapering point, as
the acumen of a leaf or of the corolla
keel of a leguminous plant.

Alliaceous: Of or pertaining to the onion
genus (Allium) ; having the charac-
teristic odor and taste of that genus.

Arillate: Having an aril; of or per-
taining to an aril.

Caruncle: An outgrowth or excrescence
of the seed-coat at or near the hilum.

Carunculate: Having a caruncle.

Extrorse: Turned outward; said es-
pecially of anthers that face outwards
from the pistil and floral axis, as the
extrorse anthers of lilies.

Furfuraceous: Branny or scurfy; cov-
ered with a meal-like scurf or powder
(Latin, furfur, bran).

Phenology: The science dealing with
the effects of climate on plant and
animal life, particularly with respect
to periodical phenomena such as the
seasonal development, budding, leaf-
ing. flowering and fruiting of plants,
ete.

Pod: A capsule; a dry seed-vessel, es-
pecially if several-seeded and de-
hiscent. Used originally of legumes,
as a pea pod.

Rhachis. See Rachis.

Septicidal: Dividing at the partitions
(septa); said especially of fruiting
capsules which open (dehisce) at ma-
turity into the separate carpels by
splitting through the partitions, as
the septicidal capsules of Labrador-
tea and rhododendron.

Involucrate: Provided with an invo-| Septifragal: Said of capsules or pods

luere, as the involucrate flowers of|
flowering dogwood.

Loculicidal: Said of a capsule which
splits (dehisces), prior to discharging
its seed, down the middle of the back
(dorsal sutures) of each carpel cell
(loculus), as the loculicidal pods of
a lily. Compare septicidal.

Metonym: Literally, a later name. A
Synonymous name rendered invalid by
the existence of an earlier, valid name
for the same species or other plant
group. Thus, Agropyron occidentale
Scribner (Dec., 1900) is a metonym
of A. smithii Rydberg (Feb., 1900).

whose valves in opening (dehiscing)
break away from the _ partitions
(septa), as the septifragal capsule of
the common morning-glory (Ipomoea
purpurea). 5

Sterigma (pl. -ta): A stalk or support;
said especially of the woody leaf-
bases of spruces and Douglas-fir
which persist on and roughen the
twigs, and of the stalklike supports
of certain reproductive cells (co-
nidia) of many fungi.

Strophiole: An appendage attached to
the base of certain seeds. Often used
as a synonym for caruncle.

U. S. GOVERNMENT PRINTING OFFICE : O—1950

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