Lavatera L.

6. Lavatera L. 1

Herbs or soft-wooded shrubs, usually stellate-pubescent. Flowers solitary or in clusters in the leaf-axils. Epicalyx-segments 3, more or less united at the base, at least in bud. Petals emarginate. Stigmas lateral, filiform. F ruita schizocarp; mericarps numerous, 1-seeded, usually indéhiscent, arranged in a single whorl.

The separation of this genus from Malva on the basis of its epicalyx-segments united at the base is very unsatisfactory, as in at least two species, traditionally assigned to Lavatera by their general facies, the epicalyx-segments in the fully expanded flower are virtually free. No better taxonomic treatment has, however, been so far proposed.

The compound hairs in this genus are described as stellate when they have numerous branches radiating in all directions, and as fasciculate when the branches, which are usually fewer and longer, are only slightly divergent.

1 Flowers in clusters

2 Indumentum including simple, glandular hairs; stipules broad, sometimes amplexicaul 11. triloba 2 Indumentum without simple, glandular hairs; stipules narrow

3 Epicalyx-segments longer than sepals, at least in fruit; stems woody in lower part 3. arborea 3 Epicalyx-segments shorter than sepals; stems herbaceous

4 Sepals strongly accrescent; mericarps ridged, with flat dorsal face and sharp, ± denticulate angles 2. mauritanica 4 Sepals only slightly accrescent; mericarps smooth or slightly ridged; dorsal face and angles rounded 1. eretica 1 Flowers solitary (rarely in pairs) in leaf-axils

5 Annual; stems not densely tomentose

6 Central axis of fruit expanded above to a disc which covers and conceals the ripe mericarps; stem hispid with simple or few-rayed, deflexed hairs 10. trimestris 6 Central axis of fruit not expanded above mericarps; stem sparsely and minutely stellate-pubescent 9. punctata 5 Perennial; stems densely tomentose, at least when young

7 Leaves ovate-lanceolate or -oblong, about twice as long as wide, not lobed 5. oblongifolia 7 Lower leaves nearly as long as wide; upper leaves usually lobed

8 All leaves suborbicular, scarcely lobed; mericarps with concave dorsal face and very sharp angles 4. maritima 8 At least the middle leaves distinctly 3- to 5-lobed; mericarps with rounded dorsal face and angles

9 Herb; pedicels usually more than 1 cm at anthesis and more than 1-3 cm in fruit 8. thuringiaca 9 Shrub; pedicels not more than 1 cm at anthesis and 1-3 cm

in fruit

10 Epicalyx invaginated at insertion of pedicel, its segments shorter than the sepals; mericarps glabrous

7. bryoniifolia 10 Epicalyx not invaginated at insertion of pedicel, its segments ± equalling the sepals; mericarps hispid or tomentose 6. olbia