Flora of North America species comparison

diffuse, upper portion not enlarged.

diffuse, upper portion not enlarged.

nearly spheric to more often cylindric or long cylindric, 5–30 × 5–7 cm, firm;

tubercles 5–12 × 3–7 mm;

axils woolly, bearing 4–15 bristles (0 in young growth) as long as tubercles;

cortex and pith not mucilaginous;

latex absent.

depressed-spheric to short cylindric, (1–)2–3.5 × (1.4–)2–4(–7) cm, firm;

tubercles 3–6(–8) × 2–3 mm;

axils without evident hairs;

cortex and pith not mucilaginous;

latex clear or slightly milky, sporadic, only in outer cortex.

14–26 per areole, pinkish or reddish brown to black, glabrous;

radial spines 11–22 per areole, usually white, bristlelike, 5–7 mm, stiff;

central spines (1–)3–4 per areole, abaxial 1 porrect, hooked, longer, stouter, adaxial central spines ascending with radial spines;

subcentral spines 0.

(26–)40–60(–90) per areole, in several series but all equally thin, mostly appressed, white or very pale pink, often minutely tipped pinkish brown, innocuous, bristlelike, 0.6–5(–6) × 0.05–0.1 mm, glabrous to plumose, all interpreted as radial, innermost spines shortest;

central spines 0.

10–22 mm;

outermost tepals entire or short fringed;

inner tepals cream, usually with pinkish or reddish midstripes, longer in bisexual flowers, 5.4 mm diam.;

stigma lobes yellow to greenish yellow or brownish green, 8 mm.

0.9–1.5(–2) × 0.8–1.3(–1.8) cm;

outermost tepal margins entire (or minutely and irregularly lacerate);

inner tepals white or cream, usually with sharply defined midstripes of green, yellow, tan, pink, pale purple, or reddish, 4.5–8 × 1.5–2.7 mm;

stigma lobes yellow or pale yellow-green to green, 0.3–1 mm.

bright scarlet, clavate or ovoid, 10–25(–35) × 10 mm, juicy only in fruit walls;

floral remnant persistent.

scarlet, cylindric or clavate, 10–20(–25) × (3–)4–8(–11) mm, juicy mostly in fruit walls;

floral remnant persistent.

black, 0.8 × 0.6 mm, pitted;

testa hard;

anticlinal cell walls straight (not undulate);

interstices conspicuously wider than pit diameters;

pits bowl-shaped.

black, 1–1.2[–1.4] × 0.8[–1.1] × 0.8 mm, pitted;

testa hard;

interstices equaling pit diameters;

pits bowl-shaped.

= 66.

= 22.