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A rounded, knoblike, usually terminal proturberance on a structure.
One of the rounded cells on the manubrium in the antheridia of lichens belonging to the Caliciales.



(also head) a monopodial inflorescence in plants whose main axis has thickened into a patelliform or globular surface on which small flowers are usually distributed. The flowers are tubular, ligulate, or pseudoligulate. This type of inflorescence is primarily characteristic of plants of the family Compositae (daisy, dandelion, and sunflower). It is also found among plants of the families Umbelliferae (eryngo and sanicle) and Campanulaceae (sheep's-bit). The capitulum is surrounded by a many-leaved involucre, formed by the bracts of the outer flower (in sheep's-bit) or by modified apical leaves (in Compositae). This structure aids in the pollination of the flowers. In the process of evolution, several biological adaptations occurred to prevent self-pollination. For example, the flowers open gradu-ally, and the stamens develop earlier than the pistils. The capitulum developed from the umbel as a result of the reduction of the length of the flower stem.

References in periodicals archive ?
The minimum and maximum sizes of the peduncle and capitulum of these octolasmids are given in Table I.
Fibrotic processes in the middle ear, vibratory loss between the middle ear structures, and possible deformations on the stapes capitulum may be possible factors for unsuccessful operations.
Gonostyli with long and narrow capitulum (in dorsal view), bearing a plate-shaped lateral tooth; hind margin of gonostylus convex, caudo-dorsal angle nearly right.
Subsequently, leaves, stems and inflorescences were placed in an oven at 65 [+ or -] 2 [degrees]C for 4 days, to obtain the dry mass of leaves (DML), stems (DMS), capitulum (DMC) and shoot (DMS= DML+DMS+DMC).
Caption: FIGURE 2: Surgery was indicated for both painful loosening of a radial head prosthesis and an osteochondral fracture of the capitulum humeri (white arrow).
lt;<Et electi qui successu temporis non potuerint sequi chorum, capitulum vel refectorium propter praedicta vel alias de facto omisserint, deponantur ab officio>> (n.
Moderate lipping was observed along the margins of the trochlea and capitulum of right humerus #70.
Downy mildew causes dwarfing plants and infertile capitulum which reduces productivity (Viranyi & Spring 2011).
Verum si episcopus vel eius capituli sede vacante delegatus cum inquisitore, aut inquisitor cum altero eorundem propter praemissa nequeat aut nolit personaliter convenire, possit episcopus vel eius seu capituli sede vacante delegatus inquisitori, et inquisitor episcopo vel eius delegato, seu sede vacante illi, qui ad hoc per capitulum fuerit deputatus, super filis committere vices suas vel suum significare per litteras consilium et consensum>> (Concilium Viennense, Decr.
Reduction of solar UV-B mediates changes in the Sphagnum capitulum microenvironment and the peatland microfungal community.