A Grammatical Dictionary of Botanical Latin

Trigone, the thickened corners of cells, esp. in liverwort leaves; “Spruce’s term for the thickening in the angles of the cells of the leaves in certain Hepatics, or as in collenchyms” (Jackson); (liverworts) “thickenings at the corners of cells where thin or somewhat thickened walls meet: minute to convex or nodular” (Paton); cf. collenchymatosus,-a,-um (adj.A): trigona,-ae (s.f.I), abl.sg. trigona, nom. pl. trigonae, dat. & abl. pl. trigonis [> L. cf. trigonus,-a,-um (adj.A), with three angles or sides];

- cellulae valde incrassatae trigonis minutis ad angulos auctae, cells strongly thickened with trigones (thickenings of angles) minute at the angles enlarged.

- cellulae disci foliaris trigonis gangliiformibus instructae, leaf disc cells provided with knot-like trigones.

- trigonis nullis vel inconspicuis, with trigones absent or inconspicuous.

- parietes tenues trigonis permagnis convexisque vel minutis vel absentibus, walls thin with very large and convex trigones or minute or absent.