Flora of North America Glossary
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| Term | Synonyms | Category | Limitation | Definition |
|---|---|---|---|---|
| megaphyll | = leaf, macrophyll (not recommended); > frond, needle | STRUCTURE | A principal, vegetative shoot organ borne laterally from a stem node; its vascular tissues, if any, continuous with those of the stem; undergoing no significant secondary growth; usually more or less bilaterally symmetrical; comprising a distal, usually laminar blade and/or a proximal stalk (petiole) or sheath; usually a primary site of photosynthesis. | |
| megaphyllous | = macrophyllous (not recommended) | architecture | plant | Bearing megaphylls. |
| megasporangium pl. megasporangia | = macrosporangium (not recommended) | STRUCTURE | A sporangium that produces megaspores. | |
| megaspore | = macrospore (not recommended) | STRUCTURE | A female spore; a spore of the larger of two types produced by the sporophytes of a heterosporous taxon; produced in a megasporangium; giving rise upon germination to a megagametophyte. | |
| megasporocarp | = macrosporocarp (not recommended) | STRUCTURE | A sporocarp that bears only megasporangia. | |
| megasporophyll | = macrosporophyll (not recommended); > carpel, cone scale, ovuliferous scale | STRUCTURE | A sporophyll that bears only megasporangia and, in Pinophyta, naked ovules that develop subsequently. | |
| megastrobilus pl. megastrobili | = female cone, macrostrobilus (not recommended) | STRUCTURE | A strobilus (cone) whose fertile organs are all megasporophylls. | |
| membranaceous | = membranous | texture | Extremely thin, pliable, and fairly tough; like animal membrane. See also chartaceous (papery, papyraceous), pergamentaceous (parchment-like). | |
| membrane | STRUCTURE | A relatively thin layer of tissue that covers or separates other, different tissue(s) and/or empty space(s). | ||
| membranous | = membranaceous | texture | Extremely thin, pliable, and fairly tough; like animal membrane. See also chartaceous (papery, papyraceous), pergamentaceous (parchment-like). | |
| meniscoid | solid shape | Relatively thin with opposite, round, broad faces, one convex and one concave (as viewed externally), the circumferential edge angular or rounded; like a meniscus. See also discoid (disciform), lenticular (biconvex, lens-shaped), patelliform (kneecap-shaped). | ||
| mentum pl. menta | = column foot | STRUCTURE | 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. | |
| mericarp | = coccus | STRUCTURE | One of the segments of a dehisced schizocarp; usually one-seeded and itself indehiscent. | |
| …merous | architecture | compound or compound-complex structure | Having the number of equivalent component parts indicated by the prefix (e.g., petals in a corolla), or having different component sets of equivalent parts of that number in each set (e.g., calyx and corolla in a perianth); as in monomerous, oligomerous, polymerous, tetramerous, trimerous. | |
| mesocarp | STRUCTURE | The middle tissue layer of the pericarp of a fruit. | ||
| mesochilium | STRUCTURE | The central portion of a labellum (lip) that has distinct proximal, distal, and central parts; in Orchidaceae. See also epichilium, hypochilium. | ||
| microgametophyte | PLANT | A gametophyte whose fertile organs (gametangia) are all antheridia. | ||
| microphyll | STRUCTURE | 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. | ||
| microphyllous | architecture | plant | Bearing microphylls. | |
| micropyle | FEATURE | The small pore in the integuments of an ovule at its apex, through which the pollen tube grows; or the corresponding aperture or scar in the coat of the seed that develops subsequently. | ||
| microsporangium pl. microsporangia | STRUCTURE | A sporangium that produces microspores. | ||
| microspore | STRUCTURE | A male spore; a spore of the smaller of the two types produced by the sporophytes of a heterosporous taxon; produced in a microsporangium; giving rise upon germination to a microgametophyte. | ||
| microsporocarp | STRUCTURE | A sporocarp that bears only microsporangia. | ||
| microsporophyll | > cone scale | STRUCTURE | A sporophyll that bears only microsporangia. | |
| microstrobilus | = male cone | STRUCTURE | A strobilus (cone) whose fertile organs are all microsporophylls. |
Displaying 1426-1450 of 2673