"|e 
39 
§ 4. Vulgares: procumbentes vel adscendentes: articuli plerumque 
minores: aculei validi, subteretes vel nulli, albidi vel obscuriores : 
bacca clavata. 
16. O. Rarinesquit, E.in P.R.R.: diffusa ; radice fibrosa ; articulis 
obovatis vel suborbiculatis perviridibus, foliis elongatis patulis; pulvil- 
lis subremotis setas graciles rufas gerentibus plerisque inermibus ; 
aculeis paucis marginalibus validis rectis singulis erectis patulisve, uno 
alterove minore deflexo subinde adjecto, rufo variegatis; alabastro 
acuto ; ovario clavato pulvillis 20-25 stipato ; petalis 10~ 12; stig- 
matibus 7-8; bacca clavata. 
Var. MIcRosPERMA: subinermis: seminibus minoribus angustius 
marginatis. : 
Sterile, sandy, or rocky soil in the Mississippi valley, from Kentucky 
to Missouri, and from Minnesota southward: fl. May and June. — 
Joints 3-5 inches long; leaves 3-4 lines long; spines 9-12 lines 
long, sometimes entirely wanting. Flowers 24-33 inches in diame- 
ter, yellow, often with a red centre. Seed 23 lines; or in the variety 
less than 2 lines in diameter. — This species had been confounded 
with the Eastern O. vulgaris by all our botanists, with the exception 
of ae who pretended to distinguish three species, viz. O. hu- 
itosa, and O. mesacantha (sometimes erroneously 
Seeded | to Nuttall), which cannot be made out, and which I have 
again united under their author’s name.— The following is probably 
only a Southern variety of this species : — 
O. GranpIFLoRA, E.: subadscendens ; articulis majusculis ; pulvillis 
remotis; setis tenuissimis; aculeis subnullis; floris grandis ovario 
elongato ; petalis sub- a latissimis ; stigmatibus 5; bacca elongata 
clavata. 
On the Brazos, Texas. — Joints often 5-6 inches long; pulvilli 
nearly an inch apart. Flowers 44-5 inches in diameter, red in the 
centre ; petals 2 inches long or more, and 14 wide. 
Dr. Bigelow collected on his tour from Arkansas to Santa Fé sev- 
eral forms, which, though somewhat distinct, are perhaps not entitled 
to be considered species. The true O. Rafinesquii does not seem to 
occur west of the western line of Missouri and Arkansas. The West- 
ern forms or subspecies are : — 
O. crmocuiza, E. & B. in P. R. R. : diffusa ; articulis orbiculatis; 
pulvillis subremotis stramineo- seu fulvo-setosis plerisque armatis ; acu- 
leis 1-3 robustioribus albidis basi fulvis patentibus deflexisve, additis 
