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A Grammatical Dictionary of Botanical Latin

Placenta, “the place or part on which ovules originale. (obsol.) also applied to the hymenium or even spore-case of Fungals” (Lindley); “any part of the interior of the ovary which bears ovules” (Fernald 1950); the placenta occurs on the carpel surface to which the ovules (potential seeds) are attached; they are usually submarginal to the leaf margins; “a sporangium-bearing surface, as, a: the part of the carpel of a seed plant bearing ovules ... b: the point on a fern or fern ally leaf or sporophyll at which sporangia develop” (WIII); (in bryology) “the gametophyte/sporophyte interface, often containing transfer cells” (Magill 1990); ovuliferous tissue: placenta,-ae (s.f.I), abl.sg. placenta, nom. pl. placentae, gen.pl. placentarum, acc.pl. placentas, dat.& abl.pl. placentis [> L. placenta,-ae, (s.f.I) a flat cake > Gk. plakount-, plakous]; see placentation;

- capsula globosa, ovoidea v. oblonga, sub vertice poris transversis inter placentas dehiscens (B&H), the capsule globose, ovoid or oblong, below the top dehiscing with transverse pores between the placentas.

- ovula 2 ab apice vel sub apice placentae centralis pendula, ovules 2 from the apex or below the apex of the central placenta pendulous (Stearn).

- ovula in placentis numerosissima, ovules on the placentas most numerous (Stearn).

- ovula plura placentae centrali liberae sessili vel stipitatae inserta, ovules many inserted onto the central free sessile or stipitate placenta (Stearn).

- ovarium nunc uniloculare placentis 2 parietalibus, nunc biloculare placentis septo adnatis, ovary now one-chambered with 2 parietal placentas, now two-chambered with placentas joined to the partition (Stearn).

- styli placentarum numero, styles with the number of the placentas, i.e. the styles the same in number as the placentas (Stearn).

- stigmata tot quot placentae, stigmas as many as the placentas (Stearn).

- ovarium placentis parietalibus v. septis a latere v. prope parietes placentiferis divisum (B&H), ovary divided by the parietal placentas or with septa from the side or near the placenta-bearing walls.

- placentae in plerisque generibus Ficoidearum v. fere in toto Ordine e basi loculorum oriundae in angulo interiore v. liberae rémanent v. axi adnatae, quomodo quoad placentationem Caryophylleis accedunt (B&H), the placentae in many genera of the Ficoideae or almost in the entire Order arise from the base of the locules in the inner angle either remain free or are adnate to the axis, in the same way they approach, as far as the placentation is concerned, the Caryophylleae.

- placentis pulposis, with the placentae pulpy.

- sporas pyriformes ad placentam basalem affìxas gerentia (Agardh), bearing pyriform spores attached to the basal placenta.

- gemmulae placentis centralibus axin septorum marginantibus ope funiculi brevis affixae in loculis biseriatae (F.Mueller), the gemmules attached to the central placentas bordering the axis of the septas with the help of a short funiculus, biseriate [i.e. in two rows] in the locules.

- placentae tenui-clavatae e medio axeos divergentes (F. Mueller), the placentas thin-club-shaped, diverging from the middle of the axis.

- axis supra placentas setuliformis (F. Mueller), the axis above the placentas like a small bristle.

- semina obovata, placentis carnoso-pulposis immersa (B&H), the seeds obovate, embedded with the fleshy-pulpy placentae.

- drupa baccatà, endocarpium osseum v. coriaceum hinc extus filo nerviformi (placenta filiformi?) percursum apice pervium, funículo per foramen in cavitatem intromisso (B&H), drupe berrylike, the endocarpium bony or leathery from this place, externally, percurrent with a nerviform thread ([perhaps] with a filiform placenta?) perforated in the apex, with a funiculus introduced into a cavity through the foramen.

- semina in placentae processubus pulposis involuta in Geniostomo (B&H), the seeds enveloped in the pulpy processes of the placenta in Geniostomum.


- In Rhodomeleis et Chondrieis denique sunt Keramidia plerumque ovata aut urceolata, rarius subsphaerica (Rytiphloea), intra pericarpium celluloso-membranaceum apice poro regulari pertusum, sporas pyriformes ad placentam basalem affìxas gerentia (Agardh), in Rhodomeleae and Chondrieae, finally, there are keramidia, usually ovate or urceolate, more rarely subsphaerical (Rhytiphloea), within a cellulose-membranaceous pericarpium perforated by a uniform apical pore, bearing pyriform spores attached to a basal placenta.

- Sporae Coccidiorum ex endochromate cellularum, in fila clavato-articulata a placenta singula centrali egredientia coordinatarum, formantur; origo itaque Favellideis subsimilis, at placenta Coccidiorum normaliter singula et in fructu maturo adhuc detegenda (Agardh), the spores of the Coccidia are formed from the endochrome [i.e. colored cell content] of cells, co-ordered into club-shaped, jointed filamens issuing forth from a single, central placenta; and thus the origin is somewhat similar to a Favellidean [origin], but the placenta of the coccidia is normally single, and in the mature fruit thus far to be observed.

- Favellidia fere Irideae, sporas laxius cohaerentes includentia (nec ut in Halymenia arctissime conjunctas) et placenta centrali Rhodomeniae omnino destituta (Agardh), the favellidia are almost of Iridaea, enclosing the spores more laxly cohering (not as in Halymenia very closely bound together) and lack completely the central placenta of Rhodomenia.

FUNGI: other than a reference to a hymenium, mycology does not use the word ‘placenta’ (Ainsworth & Bisby; S&D);

- [fungi] placentas exhibet sparsas vel contiguas , subrotundas vel oblongas, mox teretes , mox e basi rotundata angustiore sursum aliquantum incrassatas (S&A), it displays placentas [i.e. hymenia] scattered or contiguous, somewhat round or oblong, then round-cylindrical, and then from the base rounded, more narrowly upwards somewhat thickened.

- [fungi] stroma laete ac vivide luteum, demum praesertim in placentae basi canescens, supra infraque pulverulentum (S&A), the stroma a deep and vivid yellow, then, especially at the base of the placenta [i.e. the hymenium] a whitish-gray, above and within powdery.

[fungus] the genus Placentaria Auersw. & Rabenh., in probable reference to its appearance.

Dissepimentum spurium (adj.A), abl. sg. dissepimento spurio: spurious dissepiment, a partition that does not originate from the adhesion of the sides of carpellary leaves; septum (s.n.II) spurium, abl. sg. septo spurio, appears to be a synonym, according to Bentham & Hooker; see dissepiment;

- ovarium nunc septis spuriis placentas connectentibus divisum (B&H), the ovary sometimes separated by false septa connecting the placentas.

- ovarium 1-loculare v. dissepimentis spuriis divisum placentis parietalibus. (B&H), ovary 1-locular or by false dissepiments divided by parietal placentae.

- placentae dissepimento spurio saepius connexae (B&H), the placentae more often connected by a false dissepiment.

Gemmula,-ae (s.f.I), abl. sg. gemmula, “(obsol.) the plumule; also the ovule” (Lindley).

Replum, "a frame-like placenta from which the valves fall away in dehiscence" (Jackson), especially in the Brassicaceae: replum,-i (s.n.II), abl. sg. replo; see replum.

Trophospermium,-ii (s.n.II), abl. sg. trophospermio: “(obsol.) the placenta” (Lindley).

(fungi) Postia placenta (Fomitopsidaceae). The specific epithet placenta means flat or slab-like (and is Latin for cake); a polypore with a porous, flesh-colored, pink fertile surface.


A work in progress, presently with preliminary A through R, and S, and with S (in part) through Z essentially completed.
Copyright © P. M. Eckel 2010-2018

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