needle |
< leaf, macrophyll (not recommended), megaphyll |
STRUCTURE |
|
A relatively stiff, compressed-acerose leaf; in Pinophyta. |
phyllary |
= involucral bract; < bract (broad sense) |
STRUCTURE |
|
One of the bracts composing the involucre of a capitulum (head); in Asteraceae (Compositae). |
epicalyx pl. epicalyces |
= calyculus |
STRUCTURE |
|
A whorl of bracts immediately subtending (beneath or outside) a calyx. |
primary vein |
> costa, midnerve (not recommended), midrib, midvein, rib; >< lateral vein |
STRUCTURE |
|
A strand belonging to the first order of vasculature in a leaf or other basically laminar structure. See also secondary vein, tertiary vein, veinlet. |
knee root |
|
STRUCTURE |
|
A specialized secondary root of a wetland tree, a portion of which projects above mean water level and appears to bend as a leg does at the knee, its distalmost portion being anchored in the substrate beneath the water. The knee of the root is commonly regarded as a conduit for gas exchange between root interior and atmosphere, a function whose need is posited on the basis of the highly anaerobic and saturated conditions prevailing in wetland substrates. |
exocarp |
= epicarp |
STRUCTURE |
|
The outermost tissue layer of a pericarp. |
calyx tube |
|
STRUCTURE |
|
A relatively narrow, fully connate portion of a synsepalous (gamosepalous) calyx proximal to a broader portion (limb) that comprises the distinct or connate distal portions of the sepals. |
elater 1 |
|
STRUCTURE |
|
An elongate cell with a helical, hygroscopic thickening in its wall, contained within a sporangium, expanding and contracting with changes in humidity and aiding dispersal of the spores; esp. in Hepaticae. |
gynandrium pl. gynandria |
= column, gynostemium |
STRUCTURE |
|
A central floral structure consisting of the partly to wholly fused (connate and adnate) androecium and gynoecium; esp. in Orchidaceae. |
ocrea pl. ocreae var. ochrea |
|
STRUCTURE |
|
A tubular sheath that encircles a stem at a node, subtending a petiole; thought to have arisen evolutionarily by lateral fusion of two stipules; in Polygonaceae. |
cilium 2 pl. cilia |
|
STRUCTURE |
|
A motile hair- or whip-like structure extending from the surface of a cell. |
barbellule |
= barbellula |
STRUCTURE |
|
A small barbel (barbella); a very diminutive barb. |
arillus pl. arilli |
= aril (strict sense); < aril (broad sense) |
STRUCTURE |
|
An appendicular structure that wholly or partly envelops a seed and is an outgrowth from the funicle or raphe, and thus is ontogenetically derived from the placenta; usually fleshy or pulpy, sometimes spongy or tufted-capillate, often brightly colored. |
pyrene 2 |
= stone |
STRUCTURE |
|
The hard seed of a drupelet; esp. in Rosaceae. |
microsporangium pl. microsporangia |
|
STRUCTURE |
|
A sporangium that produces microspores. |
velum pl. vela |
|
STRUCTURE |
|
A membranous adaxial flap or fold of vegetative tissue wholly or partly covering the sporangial cavity of a sporophyll; in Isoëtaceae. |
spathe |
|
STRUCTURE |
|
A usually relatively large, sometimes showy, foliose bract subtending and sometimes partially enclosing an inflorescence, esp. a spadicate one; in Liliidae (monocotyledons). |
apiculum 1 pl. apicula |
|
STRUCTURE |
|
A short, slender, angular tip that is not notably harder or stiffer than the main body of the bearing structure. See also mucro. |
lenticel |
|
STRUCTURE |
|
A specialized, anatomically distinct structure within the periderm of a stem, consisting of comparatively spongy, sometimes suberized tissue distinct from others of the periderm; extending radially through the periderm and visible as a circular to elongate discontinuity in the color, texture, and/or relief of the outer surface of the stem; serving as a conduit for gas exchange between the stem interior and the atmosphere. |
cupule |
|
STRUCTURE |
|
A cup-like structure inserted at the base of a fruit, partially enclosing it or not; composed of a persistent, usually dried, sometimes hardened involucre, perianth, or portion thereof, the constituent parts often coalescent, yielding a unitary structure. |
phylloclade |
= cladode, cladophyll |
STRUCTURE |
|
A stem segment that functions as a leaf; often more or less compressed. |
thorn |
= spine |
STRUCTURE |
|
Any sharp, stiff, simple or branched, woody appendage having vascular tissues confluent with those of the bearing structure. "Spine" is often preferred when the appendage is homologous with a leaf or stipule, and "thorn" when it is homologous with a branch. See also prickle. |
wood |
= xylem |
STRUCTURE |
|
The water-conducting and usually main supporting tissue of a plant or portion thereof, characterized by the presence of tracheary elements (tracheids and sometimes vessel elements); the lignified tissue of a plant or component structure, composed almost entirely of secondary tissue, i.e., that derived by secondary or lateral growth from a cambium in structures a season or more old. As commonly used, the term wood generally refers only to secondary xylem, which constitutes the bulk of a mature woody stem, but it properly refers also to primary xylem, wherever found. See also sapwood, heartwood. |
epicarp |
= exocarp |
STRUCTURE |
|
The outermost tissue layer of a pericarp. |
primocane |
|
STRUCTURE |
|
A biennial or perennial stem before it has begun flowering, when the latter does not occur until at least its second season of growth; esp. in Rubus (Rosaceae). |