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margin |
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CHARACTER |
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Configuration of all or part of the periphery of a planate structure, sometimes referred to as though it were discrete and an entity in its own right for descriptive purposes. The extent of the area considered to pertain to the margin in a given case is, of necessity, subjectively determined. As a general rule, peripheral concavities that do not exceed 1/5 the distance from the generalized edge to the center or main axis of the structure are considered components of marginal configuration, deeper concavities being considered components of overall shape. The margin is sometimes considered to be only the infinitely thin boundary itself, and such a definition is probably the one most technically correct from the standpoint of geometry and general usage. However, it is inconsistent with traditional usage in descriptive botany, which treats the margin as an entity of substance both semantically and conceptually. The semantic antecedent of some descriptors is "margin," whereas the antecedent of others is the structure as a whole (e.g., leaf). |
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shoot 1 |
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STRUCTURE |
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Collectively, all those portions of a plant body that are anatomically distinct from the root, the component axes differentiated into nodes and internodes, and branching exogenously from the former. |
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anadromous |
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venation |
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Having the first lateral vein in each pinna or primary segment of the frond arise from its midvein on the side toward the apex of the frond, the pinnule or secondary segment that it leads to often disproportionately larger than the next distal ones. |
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microphyll |
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STRUCTURE |
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A small, lateral, leaf-like enation that, evolutionarily, is not a true leaf, i.e., whose vasculature, if any, consists of only a single median strand not ontogenetically integral with the vasculature of the bearing stem and not associated with leaf gaps in the stele of the stem; in Bryophyta, Psilotophyta, Lycopodiophyta, Equisetophyta. |
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ramentaceous |
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pubescence |
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Of small, fragile, scarious, planate trichomes. |
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calyculate 2 |
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architecture |
flower |
Subtended by a calyculus (epicalyx). |
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isodiametric |
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architecture |
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Of approximately constant breadth in all median planes. |
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peripheral |
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insertion |
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Upon or otherwise directly associated with the outer surfaces or regions of a three-dimensional structure. Although use of this term in two-dimensional contexts is technically correct, traditionally the term marginal is preferred in such cases. |
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anthela pl. anthelae |
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nominative |
inflorescence |
A cyme with the main axis markedly shorter than the lateral axes, appearing generally paniculate when compound; esp. in Juncaceae. |
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replicate |
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vernation |
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Each with the distal portion of its blade recurved, paralleling and contiguous with the proximal portion. |
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symbiotic |
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nutrition |
plant |
Partially dependent for essential nourishment upon other living organisms that derive some reciprocal benefit from the relationship. |
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cotyliform |
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solid shape |
perianth, calyx, corolla |
Having a short, relatively broad, cupulate tube and a well differentiated, erect limb. See also cyathiform, urceolate (urn-shaped). |
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spike |
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nominative |
inflorescence |
An elongate, determinate or usually indeterminate axis bearing sessile flowers inserted singly along it, unbranched or sometimes bearing lateral branches of the same nature. |
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weak |
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texture |
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Very pliable and unresilient. |
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erect |
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orientation |
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Perpendicular to the horizon or to the general plane of a bearing structure. |
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appressed |
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orientation |
lateral structure |
Angled at or near the base and closely flattened against the surface of the bearing structure, thus more or less parallel to it. |
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gynaecium |
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STRUCTURE |
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See gynoecium. |
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ridged |
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solid shape |
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Having one or more ridges; esp. fruits of Apiaceae (Umbelliferae). |
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zygomorphic |
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architecture |
perianth, calyx, corolla |
Bilaterally symmetric; divisible into two essentially equal portions along only one median logitudinal plane. |
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faceted |
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solid shape |
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Having numerous, relatively small, flat or shallowly curved portions of the external surface that are bounded by more or less distinct angular discontinuities in that surface. |
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haustorium pl. haustoria |
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STRUCTURE |
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An absorbing and anchoring organ, often root-like, excrescent from a vegetative part of a parasitic or hemiparasitic plant, by which the plant communicates intimately with and derives sustenance and support from its host plant, into whose tissues the haustorium intrudes. |
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obdeltate |
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plane shape |
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Approximately equilaterally triangular, broadest distally, and regularly attenuate to an angular base; inversely deltate; equilaterally cuneate. |
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cymule |
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nominative |
inflorescence |
A diminutive cyme, with few flowers, few or no branches, and short axes. |
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porous |
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porosity |
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Having vessels present. |
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staminodial |
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insertion |
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Upon or otherwise directly associated with the staminodes. |
