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rostrum 2 pl. rostra |
= beak |
STRUCTURE |
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The inner, horn-like segment of a coronal lobe; esp. in Asclepiadaceae. |
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mentum pl. menta |
= column foot |
STRUCTURE |
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A lateral, often nectariferous protrusion from the proximal portion of a column, opposite the labellum, projecting in front of the rest of the flower; in Orchidaceae. |
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cross-vein |
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STRUCTURE |
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A relatively short, secondary or higher-order vein that runs directly between two veins of the next lower order, intersecting them more or less perpendicularly. |
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prophyll(um) pl. prophylls, prophylla |
= bracteole, bractlet; < bract |
STRUCTURE |
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A second- or higher-order bract within, and subtending some portion of, an aggregate branching structure, especially when subtending a flower. |
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rhizome |
= rootstock |
STRUCTURE |
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An underground, usually horizontal stem, often superficially resembling a root but easily distinguished by the presence of nodes, from which it branches exogenously to produce the aboveground portion(s) of the shoot. |
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adventitious bud |
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STRUCTURE |
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A vegetative or floral bud that arises directly from a root or from some site on a shoot other than a leaf axil or stem apex. |
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lenticel |
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STRUCTURE |
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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. |
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flagellum pl. flagella |
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STRUCTURE |
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A very slender whip-like structure that extends from the main body of an antherozoid and, by active undulation, propels the cell through a liquid medium. |
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stilt root |
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STRUCTURE |
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A relatively stout or strong adventitious root arising from a woody stem branch and extending downward directly toward the substrate, within which it ultimately becomes anchored, thus supporting the branch of origin; as in some Ficus (Moraceae). |
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annulus 1 pl. annuli |
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STRUCTURE |
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A small ring-like protrusion from the strobilar stalk near its base and below the lowermost sporangiophores, sometimes bearing small sporangia; esp. in Equisetum. |
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carina 1 pl. carinae |
= keel |
STRUCTURE |
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An elongate, median longitudinal ridge that is basically triangular in transverse section and resembles the keel of a boat; esp. in leaf blades and sheaths, glumes, lemmata, paleae, sepals, petals. |
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pinna pl. pinnae |
< leaflet |
STRUCTURE |
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One of the first-order divisions or leaflets of a pinnate frond; in Polypodiophyta. See also pinnule. |
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fertile frond |
< spore leaf, sporophyll |
STRUCTURE |
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A frond that bears sporangia; in Polypodiophyta. See also sterile frond (trophophyll). |
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mericarp |
= coccus |
STRUCTURE |
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One of the segments of a dehisced schizocarp; usually one-seeded and itself indehiscent. |
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rhizophore |
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STRUCTURE |
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A stem branch that bears no leaves and from which roots eventually arise; esp. in Selaginellaceae. |
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sporangiophore |
< stalk |
STRUCTURE |
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A stalk that bears one or more sporangia. |
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toothlet |
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STRUCTURE |
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A diminutive tooth (dens). See also sawtooth, sawtoothlet, scallop (crena), scalloplet (crenule). |
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lip |
= labium; > labellum |
STRUCTURE |
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Any substructure that resembles a lip, especially a portion of a perianth, calyx or corolla. |
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veinlet |
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STRUCTURE |
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A strand belonging to the ultimate (least in diameter) order of vasculature in a leaf or other basically laminar structure when that order consists of strands ending freely within areoles and/or connecting distally by pairs across areoles; absent in some taxa. See also costa (rib), lateral vein, midvein (midnerve, midrib), primary vein, secondary vein, tertiary vein, vein (nerve). |
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adventitious root |
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STRUCTURE |
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A root that arises laterally from some part of a shoot, often from the lower portion of a main stem. |
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articulation |
= joint |
STRUCTURE |
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A distinct, relatively narrow zone of demarcation between adjacent main portions of an elongate structure, often thicker than the rest of the structure and sometimes a site of eventual abscission. |
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cilium 1 pl. cilia |
> capillus, hair; >< trichome |
STRUCTURE |
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A hair-like trichome or other surficial process. |
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sperm |
> antherozoid, spermatozoid |
STRUCTURE |
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A male gamete. |
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plantlet |
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STRUCTURE |
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A juvenile, complete plant produced asexually by budding, as from the leaf margin in some Kalanchoë (Crassulaceae); this term is usually applied only while such vegetatively produced offspring remain attached to the plant of origin. |
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lanceoloid |
= lancehead-shaped, lanciform |
solid shape |
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Considerably longer than broad, compressed or not, broadest near the base and somewhat concavely attenuate to the apex, the attenuation in all median longitudinal planes or else largely confined to one, depending upon the extent of compression, if any. See also oblanceoloid (oblanciform). |
