Flora of North America species comparison

internodes short, leaves crowded at rhizome apex (or internodes somewhat elongate, leaves scarcely crowded in var. arifolia and var. callifolia growing in wet places).

blade commonly variegate, triangular-sagittate to subhastate, infrequently ovate-sagittate to deltate.

blade unlobed, margins entire.

terminal or axillary, racemes or solitary flowers, rarely fan-shaped cymes.

calyx tube narrowly to broadly urceolate-campanulate or ovoid, 12-30 × 6-12 mm, inner surface smooth;

lobes erect or spreading, 2-8 × 2-9 mm, adaxially puberulent;

stamen connective extending slightly beyond pollen sacs;

ovary ca. 1/3-inferior;

ovules ca. 6 per locule;

styles 2-cleft to stigma.

bisexual;

calyx enlarged, petaloid, usually tubular, [1-,] 3-, [6-, rarely 5-]merous, lobes valvate;

corolla usually reduced to scales or absent;

stamens 5, 6, or 12 [multiples of 3 or 5], free or adnate to styles and stigmas, forming gynostemium;

anthers extrorse;

pistil 1, 4-6-carpellate;

ovary inferior, partly inferior, or superior;

placentation axile (and ovaries 4-6-locular) or parietal;

ovules many per locule, anatropous.

capsules [follicles], regularly to irregularly loculicidal, rarely indehiscent [septicidal].

often flattened;

endosperm copious.

with broad medullary rays.