Araceae
Arum nigrum Schott
SUMMARY
Tuberous herb sprouting in spring from a discoid, vertical tuber 4-6 cm across, 2-2.5 cm thick. Petioles subterete, 11-22.5 cm long, 4-6 mm wide, deep green with slight purple staining basally. Leaf-blade sagittate-hastate to broadly sagitate, apex acute, 9.5-21 cm long, 7.5-18 cm wide, glossy deep green. INFLORESCENCE smelling strongly of horse-dung. Peduncle much shorter than the leaves, terete, 5-9 cm long, 5-10 mm wide, bright mid-green. Spathe 12.5-20.5 cm long; spathe-tube oblong-cylindric, 4-5.5 cm long, 1.5-2.5 cm wide, constricted apically, exterior green basally, this colour extending c. ? the way up the mid-vein, otherwise very dark purple, the margins darker still, interior pale green basally, darkening c.½-way up to mid-green stained deep purple; spathe-limb broadly elliptic, 9-14 cm long, 3-8.5 cm wide, somewhat cucullate, minutely acuminate, externally glossy deep purple with greenish mottling towards the apex, interior deep purple. Spadix c. ½ as long as the spathe-limb, 8.5-13 cm in total length; appendix clavate to stoutly-cylindric, long-stipitate , 5.5-9.5 cm long, 5-10 mm wide, sooty-purple , tinged with purple apically. Staminodes in 2 whorls forming a zone 2-4 mm long; bristles subulate, stiff, 5-7 mm long, violet to dark purple; bases bulbifrom, verrucate, purplish yellow. Interstices : upper 2.5-3 mm long, ± smooth, dull yellow; lower 0.5-1 mm long, deeply and regularly longitudinally grooved, dull yellow, stained with purple. Staminate flowers in an oblong zone 8-9 mm long, 7-8 mm wide; anthers and connectives pale purple. Pistillodes in 1 whorl forming a zone 1-1.5 mm long; bristles subulate, stiff, 55-7 mm long, deep violet; bases massively conic, verrucate, dark yellow, stained with purple. Pistillate flowers in a cylindric cluster, 13-15 mm long; ovaries oblong, 2.5-3 mm long, pale yellow, upper ? violet; stigma pale grey-mauve. Fruiting spike oblong-cylindric, 3.5-5 cm long, 2-2.5 cm wide; berries pyriform, 3-9 mm long, 3-4 mm wide. Germination epigeal.