A Grammatical Dictionary of Botanical Latin

dextrorsum (adv.), also dextrorsus (adv.) or dextrovorsum (adv.) or dextroversum (adv.): towards the right, twisted to the right as viewed from the side, dextrorse [dexter + versus]; opp. sinistrorsum (adv.), twisted to the left; cf. twining; cf. longitrorsum (adv.), also longitrorsus (adv.), longitudinally, lengthwise;

- [lichen] TABULA II , fig. 4: ‘a’ thallus statu húmido (auctus 26 diametris), sinistrórsum individuum spermogoniferum, dextrorsum individuum apotheciiferum (Nyl.), plate II, figure 4: ‘a’ the thallus in a moist condition (magnified by 26 diameters), [sc. looking] to the left a spermogonium-bearing individual, to the right an apothecium-bearing individual.

- caulis infra sinistrorsum (externe visus) infra destrorsum volubilis, stem below to the left (seen from the outside) above, to the right twining.

- ovarium sessile v. raro stipitatum, e carpellis 2 (rarissime 3-4) arcte connatis, dextrorsum et sinistrórsum dispositis constans (B&H), the ovary is sessile or rarely stalked, composed of two (very rarely 3-4) closely connate carpels, arranged toward the right and left.

- arbusculse vel frutices scandentes saepius dextrorsam volubiles, (DeCandolle), small trees or shrubs climbing very often twining to the right.

- limbus 4 - 5 partitus, lobis contortis dextrorsum rarius sinistrórsum obtegentibus rarissime aliter imbricatis v. in Menyantheis induplicato- valvatis (B&H), the limb 4-5-parted, with the covering lobes contorted toward the right more rarely to the left very rarely otherwise imbricate or in Menyantheae induplicate-valved.

NOTE: antihelicte (adv.): anti-clockwise, in a direction passing from left to right, dextrorse (in the sense of Eichler, A. Gray, etc.), sinistrorse (in the sense of de Candolle, etc.) (Stearn).

NOTE: helicte (adv.): clockwise, in a direction passing from right to left when seen from the outside, sinistrorse (in the sense of Eichler, A. Gray, etc.), dextrorse (in the sense of de Candolle, etc.)' (Stearn).

dextrorsum volubilis,-e (adj.B): “twisting to the right” (Lindley).