centralium pl. centralia |
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FEATURE |
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A central longitudinal cavity within the seed; esp. in Arecaceae (Palmae). |
cloying |
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odor |
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Sickeningly sweet. |
flesh |
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STRUCTURE |
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Tissue that is fairly firm and dense, juicy or at least moist, and easily cut. |
prothallus pl. prothalli |
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STRUCTURE |
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A very diminutive thallus that is reproductively mature and undergoes no further growth; in Polypodiophyta, Pinophyta. |
gemma pl. gemmae |
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STRUCTURE |
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A vegetative propagule by which a gametophyte reproduces asexually; produced by a process analogous to budding, from a more or less cupulate specialized area (gemmae cup) on the surface of the plant body (thallus); in Psilotophyta, Lycopodiophyta, Equisetophyta, Polypodiophyta. |
circinate 1 |
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solid shape |
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Terete and rolled downward from the apex in a tight coil. |
praemorse |
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apex |
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Truncate with the distal margin irregular or ragged, as if chewed. |
comose |
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pubescence |
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Bearing a prominent single tuft of relatively long and slender, flexible, capillate trichomes (coma). |
rhipidiate |
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architecture |
inflorescence |
Comprising one or more rhipidia. |
reduced |
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size |
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Unusually or unexpectedly small. |
heartwood |
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STRUCTURE |
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The senescent inner or central portion of the wood (xylem) of an older stem or root, its cells no longer living, in which conduction has ceased and primary reserve materials are no longer stored; often containing terminal metabolic products; usually darker in color than the living, conducting sapwood that encircles it. |
aciculate |
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coloration |
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Having fine, irregularly oriented, straight streaks of contrasting hue and/or intensity. |
hydathode |
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STRUCTURE |
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A multicellular, anatomically distinctive structure located within a leaf at its periphery, its cells surrounding a central canal that opens to the exterior, through which water is actively discharged under humid conditions that impede the rate of transpiration; this liquid discharge is termed guttation. |
seed |
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STRUCTURE |
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A mature or ripened ovule containing an embryonic sporophyte and a nutritive tissue (endosperm or perisperm) with stored food that sustains the initial growth of the embryo upon germination, except when such food reserve is stored instead in the cotyledon(s) of the embryo itself, these enclosed by one or two integuments (the testa), the whole serving as a propagule. A fertile seed (one containing a viable embryo) normally results from sexual fertilization of an egg by a sperm; however, fertile seeds are sometimes produced asexually by apomictic processes (e.g., parthenogenesis). |
involute 2 |
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vernation |
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Each rolled adaxially from the lateral margins. |
scaly 2 |
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architecture |
bud, bulb |
Invested by scale-like (squamiform) structures. |
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. |
concentric |
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position |
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Having a center or axis of symmetry coincident with that of the context of reference. |
lanulose |
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pubescence |
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Finely lanate. |
spore |
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STRUCTURE |
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A simple, usually unicellular, sometimes oligocellular propagule derived by meiotic division of a diploid (2n chromosomes) sporocyte within a sporangium, thus of haploid (n chromosomes) genetic constitution. A spore constitutes the first ontogenetic stage of a gametophytic generation and gives rise to a usually multicellular gametophyte upon germination. Though technically present in seed-bearing plants, by itself it is descriptively significant only in those taxa that do not produce seeds. |
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. |
spiculate |
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relief |
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Having small, fine, stiff, acute protrusions that resemble little spikes. See also scabridulous (scabrellate, scabrellous, which is not clearly distinct in its application. |
costule |
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STRUCTURE |
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A longitudinal primary vein in a diminutive laminar structure, such as the blade of a leaflet, pinna or pinnule; a diminutive costa (rib). |
microsporangium pl. microsporangia |
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STRUCTURE |
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A sporangium that produces microspores. |
barbellulate |
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architecture |
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Bearing one or more barbellules (barbellulae). |