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. |
calyculus 2 pl. calyculi |
|
STRUCTURE |
|
Collectively the bractlets (bracteoles) sometimes subtending (beneath or outside) the involucre in a capitulum (head); in Asteraceae (Compositae). |
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. |
viscidium pl. viscidia |
|
STRUCTURE |
|
A small, viscid, glandular body of rostellar origin that becomes connected with a pollinium caudicle, either directly or through an intervening stipe, by which the pollinium attaches to a pollinating insect; in Orchidaceae. |
gynaecium |
|
STRUCTURE |
|
See gynoecium. |
pollinarium pl. pollinaria |
|
STRUCTURE |
|
A pollinium together with, when present, its stipe and viscidium; the entire unit of pollinium dispersal. |
cilium 1 pl. cilia |
> capillus, hair; >< trichome |
STRUCTURE |
|
A hair-like trichome or other surficial process. |
ochrea |
|
STRUCTURE |
|
See ocrea. |
barbel |
= barbella |
STRUCTURE |
|
A small barb. |
division |
? lobe, segment |
STRUCTURE |
|
Any generally convex, major peripheral protrusion or component sector that is delimited by concavities in the surface or margin and that is not proximally distinct from the remainder of the whole. |
pyrene 1 |
= stone |
STRUCTURE |
|
The hard inner portion of a drupe, consisting of osseous endocarp and included seed. |
velamen pl. velamina |
|
STRUCTURE |
|
A thin, often chartaceous (papery, papyraceous) or pergamentaceous (parchment-like), outermost tissue layer of an aerial root; esp. in Orchidaceae. |
bulbil |
= bulblet |
STRUCTURE |
|
A small bulb-like structure produced from a sterile or fertile plant structure other than a bulb, usually within a leaf axil, leaf sinus, or inflorescence, serving as a vegetative propagule. |
involucral bract |
= phyllary; < bract (broad sense) |
STRUCTURE |
|
One of the bracts composing the involucre of a capitulum (head,); in Asteraceae (Compositae). |
arillode |
< aril (broad sense) |
STRUCTURE |
|
A "false" aril; an appendicular structure that wholly or partly envelops a seed and is produced from or a modification of the outer integument or (in some Pinophyta) a subtending involucre, but not from the funicle or raphe, and thus is not ontogenetically derived from the placenta; usually fleshy or pulpy, sometimes spongy or tufted-capillate, often brightly colored. |
translator arm |
= caudicle |
STRUCTURE |
|
An attenuate end portion by which a pollinium adheres to a pollinating insect, either directly or by means of a terminal viscidium, the latter, when present, sometimes attached by an intervening stipe; esp. in Asclepiadaceae, Orchidaceae. |
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. |
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. |
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). |
calyptra pl. calyptrae |
|
STRUCTURE |
|
A distal hood- or lid-like portion that detaches as a unit from the remainder of the structure; esp. in some Papaveraceae the unopened calyx that separates from the rest of the flower at anthesis. |
exocarp |
= epicarp |
STRUCTURE |
|
The outermost tissue layer of a pericarp. |
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. |
cilium 2 pl. cilia |
|
STRUCTURE |
|
A motile hair- or whip-like structure extending from the surface of a cell. |