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Displaying 1 - 60 out of 69 Object(s)
Term Definition
Compound leaf Referring to a leaf which is divided into smaller units; i.e., leaflets. Opposite of simple. Leaf complexity and position. Drawing by B. Angell.
Cotyledons foliaceous (=cotyledons leaf-like) Referring to cotyledons that are not carnose but instead are thin and leaf-like. In the Sapotaceae, species with foliaceous cotyledons generall have endosperm. Seedling features of a Sapotaceae with foliaceous cotyledons. Photo by S. A. Mori.
Cotyledons leaf-like Cotyledons that look like leaves. Cultivated seedling of Couroupita guianensis.   Photo by S. A. Mori.
Even-pinnate leaf Pinnately compound leaf with an even number of leaflets; i.e., without a terminal leaflet. Same as parapinnate. Pinnately compound leaves. Drawing by Bobbi Angell.
Imparipinnate leaf Pinnate with an uneven number of leaflets, i.e., with a terminal leaflet. Same as odd pinnate. Pinnately compound leaves. Drawing by Bobbi Angell.
Leaf A green, expanded stucture usually consisiting of a petiole and a blade but sometimes without a petiole in which photosynthesis takes place. When a petiole is absent the leaf is called sessile. Craspedodromous leaf venation. Photo by C. A. Gracie.
Leaf apex acuminate Gradually tapering to an acute apex with the sides being concave. Leaf apices. Drawing by M. Sashital.
Leaf apex acute Sharp; usually referring to the apex of a flattened structure (such as a leaf) in which the two sides are straight and, when they meet, form an angle that is always less than 90° Leaf apices. Drawing by M. Sashital.
Leaf apex attenuate Tapering very gradually to a narrow tip. Leaf apices. Drawing by M. Sashital.
Leaf apex emarginate Markedly notched, such as the apex of a leaf or other structure. Leaf apices. Drawing by M. Sashital.
Leaf apex mucronate A sharp point at the apex of a leaf or a similar structure, e.g., a bract. Leaf apices. Drawing by M. Sashital.
Leaf apex obtuse Blunt, usually referring to the apex of a flattened structure (such as a leaf) in which the two sides are straight and, when they meet, form an angle greater than 90°. Leaf apices. Drawing by M. Sashital.
Leaf apex retuse Notched slightly at the apex. Leaf apices. Drawing by M. Sashital.
Leaf apex rounded Referring to a leaf blade base that is curved at the apex with an angle greater than 90 degrees at the point where the two sides meet. Leaf apices. Drawing by M. Sashital.
Leaf apex truncate Referring to an apex or base that terminates abruptly in a nearly straight horizontal edge. Leaf apices. Drawing by M. Sashital.
Leaf asymmetrical Referring to the form of a leaf in relation to the midrib, if the blade on each side of the midrib is unequal the leaf is asymmetrical. Leaf symmetry. Drawing by M. Sashital.
Leaf base acute Sharp; referring to the base of a leaf blade in which the two sides are straight and, when they meet, form an angle that is always less than 90°. Leaf blade bases. Drawing by M. Manisha.
Leaf base asymmetric Referring to a leaf base in which the two sides do not attach to the petiole at the same place, one is attached than the other. Some leaf features of witch hazel. Photo by S. A. Mori.
Leaf base cordate Heart-shaped at the base of a leaf blade. A cordate leaf blade always has a cordate base but a cordate leaf base may not always be associated with a cordate leaf blade. Leaf blade bases. Drawing by M. Manisha.
Leaf base cuneate Wedge-shaped; referring to the base of a leaf blade of which the angle formed by the meeting of the margins is less than 90°. Leaf blade bases. Drawing by M. Manisha.
Leaf base decurrent Referring to a leaf blade base that extends down the petiole. Leaf blade bases. Drawing by M. Manisha.
Leaf base lobate (lobed) A rounded projection arising from the base of a leaf blade. Leaf blade bases. Drawing by M. Manisha.
Leaf base obtuse Blunt, referring to the the base of a leaf blade in which the two sides are straight and, when they meet, form an angle greater than 90°. Leaf blade bases. Drawing by M. Manisha.
Leaf base rounded Referring to a leaf blade base that is curved at the apex with an angle greater than 90 degrees at the point where the two sides meet. Leaf blade bases. Drawing by M. Manisha.
Leaf base sagittate The base of a leaf blade shaped like an arrowhead. A sagittate leaf blade base. Drawing by B. Angell.
Leaf base truncate Referring to the base of a leaf blade that terminates abruptly in a nearly straight horizontal edge. Leaf blade bases. Drawing by M. Manisha.
Leaf blade The expanded portion of a leaf, it and the petiole combined equal the leaf. Same as lamina. Actinodromous leaf venation. Photo by S. A. Mori.
Leaf flush The expansion of new leaves. Leaf flush of Grias subbullata. Photo by X. Cornejo.
Leaf gap A region of parenchyma in the vascular tissue of a stem that is located above the level where a leaf trace diverges from the stem toward the leaf. Stem anatomy of Gustavia augusta. Photo by C. Carollo.
Leaf lamina The expanded portion of a leaf, it and the petiole combined equal the leaf. Same as leaf blade. Stem anatomy of Gustavia augusta. Photo by C. Carollo.
Leaf margin crenate Referring to a leaf blade margin with teeth rounded at the apex. Compare with serrate. Leaf margins. Drawing by M. Sashital.
Leaf margin dentate Referring to a leaf margin with sharp teeth oriented at right angles to the central axis of the leaf blade. Leaf margins. Drawing by M. Sashital.
Leaf margin doubly serrate Leaf blades with margins with sharp teeth oriented toward the apex with each touth in turn with a smaller tooth. Leaf margins. Drawing by M. Sashital.
Leaf margin entire Referring to leaf blade margins that are smooth, i.e., they have no serrations or crenations. Leaves of Dioscorea villosa. Photo by S. A. Mori.
Leaf margin erose Referring to leaf blade margin that is jagged, i.e., uneven but not with well-defined teeth. Leaf margins. Drawing by M. Sashital.
Leaf margin lobed Referring to rounded projections arising from the margins of a leaf blade that are cut less than one-half the distance to the midrib of the leaf blade, e.g., the leaves of the white oak group. Leaf margins. Drawing by M. Sashital.
Leaf margin serrate Leaf blades with margins with sharp teeth oriented toward the apex. Leaf margins. Drawing by M. Sashital.
Leaf opposed Referring to an inflorescence, infructescence, or tendril arising from the stem opposite a leaf. Young inflorescences of Piper urophyllum. Photo by R. Aguilar.
Leaf scar The scar left on a stem when a leaf falls. Leaf scars of Grias subbullata. Photo by X. Cornejo.
Leaf sheath Tubular, inrolled base of a leaf blade or petiole that surrounds the node and a portion of the internode; e.g., in the Cyperaceae, Poaceae, and many other monocotyledons as well as in some dicotyledons. Nodes of two species of Cyperaceae. Drawing by B. angell.
Leaf symmetrical Referring to the form of a leaf with the blade equal on each side of the midrib. Leaf symmetry. Drawing by M. Sashital.
Leaf symmetry Referring to the form of a leaf in relation to the midrib, if the blade on each side of the midrib is equal the leaf is symmetrical and if the blades on each side of the midrib are not equal the leaf is asymmetrical. Leaf symmetry. Drawing by M. Sashital.
Leaf venation acrodromous Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from either the base or above it; perfect acrodromous is used when these veins converge near the apex; e.g., Strychnos (Loganiaceae); imperfect acrodromous is used when these veins do not converge at the apex. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Ciliate leaf margin. Photo by S. A. Mori.
Leaf venation actinodromous Referring to a type of leaf venation in which three or more primary veins diverge radially from a single point either at (basal actinodromous) or above (suprabasal actinodrmous) the point of attachment of the petiole. The primary veins can either converge at the apex (perfect actinodromous) or not converge at the apex (imperfect actinodromous). Based on Hickey, 1973. For more information on leaf venation see Ellis et al., 2009. Actinodromous leaf venation. Photo by S. A. Mori.
Leaf venation basal acrodromous Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from the base and converge at or close to the apex.. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Leaf venation acrodromous. Drawing by M. Sashital.
Leaf venation basal actinodromous Referring to a type of leaf venation in which three or more primary veins diverge radially from a single point at point of attachment of the petiole. Actinodromous leaf venation. Photo by S. A. Mori.
Leaf venation brochidodromous Referring to a type of leaf venation in which the secondary veins do not terminate at the margin but join to form a series of prominent arches that form a submarginal nerve; for example, in many Myrtaceae. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Camptodromous leaf venation.
Leaf venation brochidodromous festooned Referring to a type of leaf venation in which the secondary veins do not terminate at the margin but join to form a series of prominent arches that form a submarginal nerve and, in addtion, the secondary veins possess closed loops toward their apices. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Leaf venation festooned brochidodromous. Photos by C. A. Gracie.
Leaf venation camptodromous Referring to a type of leaf venation in which the secondary veins do not terminate at the margin; in one type each secondary vein connects with the seconday vein above it (brochidodromous) and in the other type the secondary veins do not connect with the secondary vein above it (eucamtodromous). Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Camptodromous leaf venation.
Leaf venation campylodromous Referring to a type of leaf venation in which a series of more or less equal primary veins originate from a common point at the base, arch upward, and reunite toward the apex; e.g., species of Aristolochia (Aristolochiaceae). Campylodromous leaf venation. Drawing by M. Sashital.
Leaf venation cladodromous Referring to a type of leaf venation in which the secondary veins branch freely before they reach the margin. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Several leaf venation types. Drawing by M. Sashital.
Leaf venation eucamptodromous Referring to a type of leaf venation in which the secondary veins do not reach the margin and do not form a series of prominent arches. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Eucamptodromous leaf venation. Drawing by M. Sashital.
Leaf venation flabellate Referring to leaf venation with several to many fine basal veins that spread out from the base like a fan and divide somewhat toward the apex. Based on Ellis et al., 2009. Flabellate (flabelliform) leaves and short shorts. Photos by S. A. Mori.
Leaf venation hyphodromous Referring to a leaf blade with all but the midvein absent or not visible because the leaf blade is too fleshy for them to be seen. Hyphodromous leaf venation. Drawing by M. Sashital.
Leaf venation imperfect acrodromous Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from or above the base and do not converge at the apex. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Hyphodromous leaf venation. Drawing by M. Sashital.
Leaf venation mixed craspedodromous Referring to a type of leaf venation in which some of the secondary veins terminate at the leaf margins and the remainder of the secondary veins do not, e.g. half of the secondary veins are craspedodromous and the other half camptodromous. Types of craspedodromous leaf venation. Drawing by M. Sashital.
Leaf venation perfect acrodromous Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from the base or above the base and converge near the apex. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Leaf venation acrodromous. Drawing by M. Sashital.
Leaf venation reticulodromous Referring to a leaf venation type in which the secondary veins form a network of veins soon after departing from the midrib. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Several leaf venation types. Drawing by M. Sashital.
Leaf venation simple craspedodromous Referring to a type of leaf venation in which all of the secondary veins terminate at the leaf margins. Craspedidromous venation of Fagus grandifolia. Image by S. A. Mori.
Leaf venation suprabasal acrodromous Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from above the base. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009. Leaf venation acrodromous. Drawing by M. Sashital.